Pulse vanilla cookies in your food processor using the S blade until fine crumbs form. Place into a mixing bowl and set aside.

Preheat oven to 350 degrees Fahrenheit (175 degrees Celsius).

Place the strawberry Jello powder into your mixer along with four tablespoons butter at room temperature. (The butter should be soft but not melted.) Beat the butter into the Jello until well combined. Add in the instant vanilla pudding and beat it into the mixture. Beat in the flour until mixed through and no white spots are left. Spread this mixture out onto a parchment-lined baking sheet. Bake for eight minutes.

Remove from oven and allow to cool for two to three minutes. Transfer baking sheet to your fridge and let the mixture cool for at least 15 minutes.

Break up the cooled Jello mixture into large pieces and transfer to your food processor. Pulse until crumbs have formed, but make sure not to overprocess so it doesn’t become too fine and powdery. Transfer the crumbs into the bowl with the vanilla cookie crumbs and mix until well-combined.

Whisk the cornstarch and water together until all the cornstarch has dissolved. Place the cornstarch mixture along with the rest of the sauce ingredients into a small saucepan over medium heat. Using a wooden spoon or rubber spatula, stir the mixture as it cooks. Bring it to a simmer and allow to simmer for five minutes, stirring constantly. Remove pan from heat and allow to cool. The mixture will thicken as it cools.

Melt the remaining six tablespoons butter and combine with the crumbs. Prepare 12 eight-ounce (225-gram) mousse cups. Spoon about two tablespoons of the crumbs into the bottom of each cup.

Pour the heavy cream into your mixer bowl and beat on high until stiff peaks form. Make sure the cream is very cold, or it won’t be stiff enough. In a second bowl, combine the cream cheese, sugar, and vanilla and mix until completely smooth and creamy. Gently fold the whipped cream into the cream cheese mixture and stir until completely combined and creamy. Transfer the mixture into a piping bag and divide about half of it among the cups to create the first layer. (You can also spoon it in.) Drizzle about a tablespoon of strawberry sauce over the cream and add several fresh strawberries, if using. Repeat with another layer of crumbs, cream, and syrup, topping lightly with remaining crumbs and garnishing with fresh strawberries, if desired.

These cups may be refrigerated up to a day or two ahead of time, but add the fresh strawberries and additional crumb topping right before serving.