Stuffed Mushrooms with Bacon & Emmental

Scrape out the gills first—that’s where all the bitterness lives. Then marinade the caps whole so they actually absorb something, not just sit there wet. This is where most people mess up.

Why You’ll Love This Stuffed Mushroom Dish

Takes 55 minutes total. That’s prep and bake, no hidden steps. Bacon gets crispy. Asparagus stays firm enough to notice it’s there. The Emmental melts into this golden crust that crackles when your fork hits it. Tastes restaurant-grade but comes together in one skillet plus one pan. Works as a side—works as the main thing too, depending on your mood. Leftovers reheat in the oven and don’t fall apart. Most stuffed portobello mushrooms get soggy an hour later. These don’t. Not immediately anyway.

What You Need for Filled Mushroom Recipe

Four large portobellos work. Eight small ones work too—just watch the bake time, probably 3-4 minutes shorter. The marinade is soy, olive oil, Worcestershire, Dijon mustard, salt, pepper. Nothing fancy. Whisk it together.

Turkey bacon. Not regular bacon—cleaner flavor, crispier when you render it right. Cut thick, about half a centimeter. Two slices, chopped into lardons. This matters because thin bacon just disappears.

Asparagus trimmed and cut small—one centimeter pieces. Red bell pepper, one small one, finely chopped. Not huge chunks. They need to cook down. One small onion, minced. Doesn’t take long.

Chicken broth. Vegetable broth if you’re avoiding chicken. About three-quarters cup. Just enough to concentrate flavor without turning everything into soup. Homemade croutons—the packaged ones are too hard, too salty. Break them into chunky pieces. Around one cup. The cheese is Emmental, grated. One and three-quarter cups. Gruyère works too if Emmental’s hard to find.

How to Make Stuffed Portobello Mushrooms

Grab a damp cloth. Wipe the mushroom caps clean. Not water. Cloth. Water makes them soggy and that’s the kiss of death.

Pop the stems out. Chop them finely—you’re adding those back into the filling. Use a spoon to scrape out the gills. That dark layer underneath. It’s bitter and nobody wants bitter. Scrape gently so the cap stays intact. Toss the gills. Keep the caps.

Mix soy sauce, olive oil, Worcestershire, mustard, salt, pepper in a bowl. Add the mushroom caps whole. Toss them around so every curve gets touched by marinade. Sit them there for about 15 minutes. The marinade won’t sink deep into the flesh—doesn’t matter. It flavors the surface, helps the browning later.

Get a skillet hot. Throw in the turkey bacon lardons. Let them render until they’re golden and actually crisp. Five minutes minimum. Don’t rush this or they stay rubbery and nobody cares that you used turkey bacon at that point. Toss in the chopped mushroom stems, the asparagus pieces, red pepper, minced onion. Season lightly. Sauté until the vegetables soften but still have some push-back to them. Three to four minutes. You want some texture.

Pour in the broth. Let it bubble. Simmer until the liquid reduces almost completely—watch this part. Stir occasionally so nothing burns on the bottom. Six to seven minutes usually. You’re concentrating flavor. Everything should look slightly damp, not swimming.

How to Get Stuffed Mushroom Filling Right

Add the croutons last. This is specific. Stir fast so they soak up the remaining juices but don’t collapse into mush. They should stay chunky, identifiable. Pull off the heat.

Get a baking sheet lined with parchment. Drain the mushrooms from their marinade—tip the caps so liquid pours out—and lay them on the sheet. Sprinkle salt and pepper inside each cap. Don’t skip this. The marinade flavored the outside. The inside still needs seasoning.

Spoon the filling into each mushroom cap. Generous. Pack it in so you can see everything stacked there. Top with shredded Emmental. Spread it across so it covers the filling and the exposed cap edges. This melts into a crust. A crunchy, brown, golden blanket.

Oven to 205°C—that’s 400°F. Slide the sheet in. Check after 18 minutes. The cheese should bubble. It should have darker specks, almost brown spots. The mushroom flesh should give when you poke it but not collapse. It’s tender, not falling apart into liquid.

If the cheese browns too fast before the mushroom softens, tent it loosely with foil. Give it another five minutes, check again. This happens if your oven runs hot.

Stuffed Mushroom Tips and Common Mistakes

The gills. Everyone forgets or skips this. Don’t. They’re bitter. Thirty seconds with a spoon changes everything.

Soggy mushrooms happen when people let them sit around after baking. Serve immediately. Hot. They’re best in the first ten minutes. After twenty they start weeping liquid and the whole thing gets sad.

Reheating works if you use the oven. Toast them back to crispness. Microwave turns the bacon rubbery and the mushroom base into something you don’t want to eat. Just don’t.

The croutons stay chunky if you add them at the very end. If you add them earlier they turn to paste. Timing matters here.

Turkey bacon versus regular bacon—turkey’s cleaner. Regular bacon works if that’s what you have. Just know it’ll taste smokier, slightly meatier. Some people prefer it. Comes down to preference.

Portobello caps versus smaller mushrooms—portobellos are easier because they’re bigger, hold more, look impressive. Smaller ones work if you want appetizer-sized. Just reduce the filling amount proportionally and shorten the bake time a few minutes.

Emmental versus Gruyère—Emmental melts smoother and browns faster. Gruyère is nuttier, browns slower. Either works. Mix them if you want. Half and half is actually better.

Stuffed Mushrooms with Bacon & Emmental

By Emma

Prep:

25 min

Cook:

30 min

Total:

55 min

Servings:

4 servings

Ingredients

• 4 large portobello mushrooms or 8 small ones
• MARINADE
• 40 ml (2 1/2 tablespoons) soy sauce
• 30 ml (2 tablespoons) olive oil
• 15 ml (1 tablespoon) Worcestershire sauce
• 5 ml (1 teaspoon) Dijon mustard
• Salt and freshly cracked black pepper
• FILLING
• 2 slices turkey bacon approx 1/2 cm thick, cut into lardons
• 400 ml (1 3/4 cups) asparagus trimmed and cut into 1 cm pieces
• 1 small red bell pepper, seeded and finely chopped
• 1 small onion, minced
• 200 ml (about 3/4 cup plus 1 tablespoon) chicken broth or vegetable broth as substitute
• 250 ml (1 cup) homemade croutons, crumbly but not powdery
• 450 ml (1 3/4 cups) grated Emmental cheese

Method

1. PREP MUSHROOMS
2. 1 Remove mushroom stems, finely chop them and set aside. Using a spoon, gently scrape out the gills - that dark layer will turn your stuffing bitter, toss it. Keep the mushroom caps intact but wipe them clean with a damp cloth; rinsing makes them soggy.
3. MARINATE
4. 2 Whisk together soy sauce, olive oil, Worcestershire, Dijon, salt, and pepper in a bowl or zip-top bag. Add the mushrooms whole. Toss well to coat every curve. Let sit for about 15 minutes — marinade won’t soak in deeply but flavors the surface, enhances browning.
5. BUILD FILLING
6. 3 In a hot skillet, render turkey bacon bits till golden and crisp, about 5 minutes—don’t rush this step or bacon ends rubbery. Toss in chopped mushroom stems, asparagus, red pepper, and onion. Season lightly with salt, pepper. Sauté till veggies soften but still give slight bite, 3-4 minutes.
7. 4 Pour in broth. Bring to bubble; simmer until liquid reduces almost dry — watch closely to avoid burning, stir occasionally, 6-7 minutes. You want concentrated flavor without soggy mix.
8. 5 Add croutons last. Stir fast so they soak up juices slightly but stay chunky, not collapsing into mush. Remove from heat.
9. ASSEMBLE & BAKE
10. 6 Drain mushrooms from marinade, place on lined baking sheet. Sprinkle salt and pepper on inside of caps. Spoon filling generously inside each.
11. 7 Top with shredded Emmental spread evenly to cover surfaces, this melts and browns, forming a crunchy blanket.
12. 8 Slide into oven preheated to 205 °C (400 °F). Check after 18 minutes, cheese should be bubbling and golden with darker specks. Mushroom flesh should be tender when poked, but not falling apart.
13. 9 If cheese browns too fast, tent loosely with foil and continue 5 minutes if needed.
14. FINISH & SERVE
15. 10 Serve immediately, hot and aromatic. Can be side with grilled steak or simple salad. Watch for soggy mushrooms if resting too long, best eaten fresh.
16. 11 Leftovers can be reheated in oven to bring cheese back to life; microwave makes rubbery bacon and soggy base.

Nutritional information

Calories

320

Protein

18g

Carbs

15g

Fat

22g

Print Recipe Save to Pinterest

Frequently Asked Questions About Stuffed Mushroom Filling Recipe

Can I prep these stuffed portobello mushrooms ahead of time? Yeah. Assemble them, cover with plastic wrap, stick in the fridge. They’ll hold for maybe six hours. Bake them straight from cold—add a minute or two to the bake time since they start colder. Don’t let them sit uncooked overnight or the mushrooms start leaking.

What if I can’t find Emmental cheese? Gruyère works. Sharp cheddar works. Fontina works. Anything that melts and browns. Avoid pre-shredded if you can—it has anti-caking powder that makes it stringy instead of creamy.

Can I use fresh asparagus instead of—wait, the recipe calls for asparagus. Right. Use fresh. Frozen asparagus has too much water, makes the filling soggy. Actually thaw it and squeeze it dry if that’s all you have. Still not ideal.

How do I know when the mushrooms are actually done? The cheese bubbles and gets golden spots. Darker is better than too pale. The mushroom flesh gives when you press it with a fork but doesn’t feel mushy all the way through. There’s still some resistance. That’s when you pull it.

What can I stuff these with instead of this filling? Sausage. Crabmeat. Spinach and feta. Breadcrumbs and herbs. The technique stays the same—render your protein first, cook your vegetables, combine, stuff, top with cheese, bake. But this recipe right here is asparagus, bacon, onion, pepper, broth, croutons, Emmental. Don’t swap too many things or you’re making a different dish.

Do I really need to marinade the caps? Helps them brown better and adds flavor to the outside. Could skip it and just season before baking. Won’t be as good but it’ll still work. The marinade sits 15 minutes so it’s not a huge time commitment.