Lemon Sundae Tart with Vanilla Ice Cream

Lemon custard goes hot over cold vanilla. That’s it. That’s the whole thing and it works because the heat matters more than you’d think.

Why You’ll Love This Lemon Sundae Tart

Takes 35 minutes total. Fifteen of that’s just stirring. Actual hands-on time? Maybe ten. No bake element except the custard—and that’s not baking, that’s heating. Everything else just sits there. Tastes like you spent three hours on it. Doesn’t feel like a tart at first, more like a sundae that remembered it had ambitions. Crumble stays crunchy for maybe five minutes before the cold and heat start fighting it out. Eat it fast or accept it’ll soften. Either way, good. Vanilla ice cream is the whole play here. Without it, you’re just eating lemon custard on a plate like some kind of person with standards.

What You Need for a Lemon Custard Tart

Sugar and cornstarch—that’s your base. The starch thickens everything. Regular sugar works. Don’t get fancy.

Eggs. Three of them. Room temperature doesn’t matter as much as people say, but it’s easier if they are.

Lemon juice. Fresh. Bottled works if that’s what you have, tastes a bit different though—more chemical, less bright. About 85 ml. That’s like two big lemons.

Butter. Melted unsalted. Not much—just 25 ml. Enough to make it rich without tasting greasy.

Vanilla ice cream. This isn’t optional. This is the thing. Get good ice cream or don’t make this.

Whipped cream for the top. Homemade or store-bought. Homemade’s better but nobody will know if you don’t tell them.

Crumble topping. Could be store-bought. Could be leftover from something else. Doesn’t really matter—it’s texture on top of texture at this point.

How to Make Lemon Custard for Your Sundae Tart

Mix the sugar and cornstarch in a saucepan first. Just combine them dry. Breaks up any lumps the cornstarch might have.

Crack the eggs into a bowl. Whisk them a bit. Add the lemon juice. Add the melted butter. Whisk until it looks smooth and combined, no visible streaks.

Pour the egg mixture into the saucepan with the sugar and cornstarch. Whisk constantly—not like you’re making meringue, just regular whisking. Keep it moving. This prevents scrambled bits from forming and makes everything thicken evenly.

Heat it. Medium heat. Not high. You’re bringing it to a boil but slowly. Takes about seven to ten minutes. The custard will start thin, then gradually go thicker. You’ll feel it happening—the whisk gets more resistance. That’s when it’s done.

It should bubble slightly once you hit boiling. One or two bubbles breaking the surface. Then stop. Pull it off heat.

Getting the Texture Right on Your Lemon Custard Tart

Transfer everything to a bowl. Let it cool at room temperature for a bit—maybe five minutes. You don’t want it cold yet, just not scalding.

Pop it in the fridge. Doesn’t need to be ice cold. Just set slightly. Fifteen minutes usually does it. Twenty if you’re not in a rush.

While that’s happening, get your sundae glasses ready. Vanilla ice cream should be cold. Whipped cream should be cold. Crumble should be… well, dry.

No Bake Tart Assembly and Serving Tips

Scoop ice cream into each glass. One or two scoops depending on how greedy you’re feeling. Pack it down a tiny bit so the custard doesn’t slide right through to the bottom.

Spoon the lemon custard over the ice cream. Spread it gently. You’re not mixing it in, just covering the top loosely. Some ice cream showing through is fine. Better, actually.

Get a piping bag. Star tip. Pipe whipped cream rosettes on top. If you don’t have a piping bag, just dollop it. Looks less fancy, tastes identical.

Crumble topping goes on last. Generous. Cover most of the whipped cream. Let some edges show. Sprinkle it everywhere.

Serve right now. Or refrigerate for five to ten minutes if you want it colder. But don’t wait longer than that—the crumble softens and becomes kind of sad.

The best part is the first bite when everything’s still in its own temperature zone. Cold ice cream. Warm-ish custard. Crunchy crumble. Then it all starts blending together and it’s still good, just different.

Lemon Sundae Tart with Vanilla Ice Cream

By Emma

Prep:

20 min

Cook:

15 min

Total:

35 min

Servings:

8 servings

Ingredients

• 170 ml sugar
• 7 ml cornstarch
• 3 eggs
• 85 ml lemon juice
• 25 ml melted unsalted butter
• vanilla ice cream
• crumble topping
• whipped cream

Method

1. LEMON CUSTARD
2. 1 Mix sugar with cornstarch in saucepan. Whisk in eggs, lemon juice, and butter until smooth. Heat gently stirring constantly with whisk. Bring to slow boil for about 7-10 minutes until thickened. Remove from heat. Transfer to bowl and let cool until lukewarm to slightly chilled. Cover and place in fridge to set slightly while preparing other components.
3. ASSEMBLY
4. 2 In sundae glasses, add one or two scoops of vanilla ice cream. Spoon lemon custard over ice cream, spreading gently. Using piping bag fitted with star tip, pipe rosettes of whipped cream on top. Sprinkle crumble topping generously over whipped cream and edges. Serve immediately or refrigerate for 5-10 minutes if preferred cooler but best enjoyed before crumble softens.

Nutritional information

Calories

250

Protein

4g

Carbs

30g

Fat

12g

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Frequently Asked Questions About Lemon Custard Tart with Vanilla Ice Cream

Can I make the lemon custard ahead of time? Yeah. Make it the day before if you want. Cover it. Keeps fine in the fridge. Just give it a stir when you’re ready to use it—might separate slightly and that’s normal.

What if my custard breaks or gets lumpy while cooking? Strain it through a fine mesh sieve. Takes two seconds and nobody knows it happened. Or it’s probably fine and you’re overthinking it.

Can I use bottled lemon juice instead of fresh? Works. Tastes sharper though. If that’s all you have, reduce it slightly—use like 75 ml instead of 85.

How long does the crumble stay crispy? Five minutes tops before the moisture from the ice cream and whipped cream starts turning it soft. That’s why you eat it fast.

Do I have to use vanilla ice cream? No bake lemon tart technically works with other flavors. Vanilla just makes sense—doesn’t compete, lets the lemon shine. Salted caramel would be weird. Pistachio would be fighting for attention. Vanilla’s the right call.

Can I make this without whipped cream? Sure. Extra ice cream instead. More custard. Whatever. The whipped cream adds a texture layer that’s nice, but it’s not essential. The lemon custard and vanilla ice cream are what matter.

How do I store leftovers? Honestly, this doesn’t really have leftovers. You either eat it or it sits there getting weird and separated. Make it fresh when you want it. Only takes 35 minutes anyway.