1-Step 1: Make the Custard Base In a medium saucepan, whisk together 3/4 cup granulated sugar, 2 whole large eggs, and 3 large egg yolks for one minute. Add 1/3 cup corn starch and whisk until smooth, then gradually whisk in 1/2 cup sweetened condensed milk and 3 cups milk. For a smoother custard, learn more about thickening techniques from a simple cornstarch guide. Cook over medium heat, whisking frequently, until it thickens and begins to boil, about 8-10 minutes, then remove from heat.

Stir in 1 tablespoon vanilla extract and 1 stick (1/2 cup) softened unsalted butter until fully mixed. Cover the custard with plastic wrap directly on the surface to avoid a skin forming, and let it cool at room temperature for one hour until barely warm. This step is crucial for the no bake Napoleon cake recipe to set properly.

2-Step 2: Prepare and Layer the Cookies Prepare the cookies by cutting larger ones in half for a better fit. Crush 3-4 cookies in a sealed bag using a rolling pin for a crumb coat. Place the springform ring over a cake platter and spread 4 heaping tablespoons of custard evenly, then arrange as many cookies as fit in one layer.

Add 5 heaping tablespoons of custard and repeat for four layers total. Spread the remaining custard over the top to seal gaps, cover with plastic wrap, and refrigerate overnight. This allows the cookies to soften in the creamy filling, mimicking traditional Napoleon cake flavors.

3-Step 3: Serve and Enjoy To serve, loosen the edges with a thin spatula, sprinkle crushed cookie crumbs on top and sides, pressing gently, and decorate with a ring of berries. For the best texture, let the cake sit out for a bit before serving.