Start by preheating your oven to 375°F and lining a baking dish with parchment paper. Melt butter and chocolate chips in a double boiler or microwave, then set aside. Combine the dry ingredients in one bowl, whisk the wet ingredients in another, and mix them together gradually. Pour the batter into the baking dish and bake for 15-20 minutes. Once cooled, crumble the cake with fork.

Blend dulce de leche with milk to form a smooth, pourable syrup. This will be used to soak the cake layers and add a caramelized sweetness.

Melt cthe hocolate and butter, then stir until smooth. Heat egg yolks, sugar, and a little water in a saucepan until they thicken slightly. Add the melted chocolate to the egg mixture and refrigerate. Whip cream until stiff peaks form, then gently fold it into the cooled chocolate mixture.

Place a tablespoon of dulce de leche syrup at the bottom of a mason jar. Add a layer of crumbled cake, drizzle it with more syrup, and top with chocolate mousse. Repeat the layers until the jar is nearly full, finishing with whipped cream, more crumbled cake, and a final syrup drizzle.

Refrigerate the jars for at least 2 hours to allow the flavors to meld beautifully. Serve chilled and enjoy!