Wash, peel, and dice the apples into roughly 1/2-inch pieces so they cook evenly.

Toss the diced apples with the granulated sugar, cinnamon, and a pinch of salt in a small bowl. This lets the sugar start drawing out juices.

Measure out the cornstarch and water into a tiny ramekin and whisk until smooth — this slurry will thicken the filling later.

Pro tip: If your apples are very tart, add an extra tablespoon of brown sugar here so the final cups taste balanced.

Heat the 2 tablespoons of butter in a small saucepan over medium heat until melted and foamy.

Add the sugared apples and cook, stirring gently, for 4–6 minutes until they begin to soften and release juices.

Sprinkle in the brown sugar and continue to cook, stirring occasionally, until the sugar dissolves and the apples look glossy.

Give the cornstarch slurry one more stir and pour it into the pan. Stir gently and cook for another 1–2 minutes until the mixture thickens and clings to the apples.

Remove from heat and let the filling cool for 8–10 minutes — it will thicken a little more as it cools.

Pro tip: Whisk the cornstarch slurry right before adding and stir continuously for the first 30–45 seconds to prevent lumps.

Place the graham crackers or shortbread cookies in a zip-top bag and crush them with a rolling pin until you have mostly fine crumbs with a few larger bits for texture.

Transfer crumbs to a mixing bowl and stir in the 2 tablespoons of melted butter until the mixture holds together when pressed between your fingers.

Taste a tiny pinch — if it’s not buttery enough for your liking, add a half tablespoon more butter.

Pro tip: Press a little of the crumb mix into the bottom of each cup to create a compact base that keeps the filling from turning soggy.

Spoon about 1–2 tablespoons of the crumb base into the bottom of each cup and gently press down.

Add a generous scoop (about 1/4 to 1/3 cup) of the warm apple filling on top of the crust layer.

Sprinkle another thin layer of crumbs over the apples for crunch and visual contrast. Repeat layers if your cups are taller, ending with crumbs or a small dollop of whipped cream.

Add any optional toppings now: a drizzle of caramel, a dusting of cinnamon, or a small piece of apple for decoration.

Serve warm right away for a cozy, pudding-like experience, or chill in the refrigerator for 30–60 minutes if you prefer a firmer set and cooler treat.

If preparing ahead, cover each cup with plastic wrap and refrigerate for up to 3 days. Add whipped cream or caramel only right before serving.

To reheat, remove topping and microwave the cup for 20–30 seconds, then add fresh whipped cream.

Pro tip: If serving to kids, warm cups are often more comforting; for take-to-school snack cups, chill them and pack the topping separately to keep things tidy.

Make sure the filling is thick, not soupy, before assembling — it should cling to the spoon.

Taste as you go (especially the crumb and filling balance) so each cup ends up perfectly sweet and spiced for your crowd.