Step 1: Make the Belgian Waffles

1. Preheat your waffle maker. Lightly grease it if needed.
2. In a large bowl, whisk together flour, baking powder, sugar, salt, and cinnamon.
3. In another bowl, beat egg whites until stiff peaks form. Set aside.
4. In a separate bowl, mix egg yolks, vegetable oil, milk, and vanilla extract.
5. Pour the wet mixture into the dry ingredients and stir until just combined.
6. Gently fold in the beaten egg whites with a spatula, being careful not to deflate them.
7. Cook the waffles according to your waffle maker’s instructions. Cool completely before assembling.

Step 2: Make the Mascarpone Cream Frosting

1. In a stand mixer, combine powdered sugar, vanilla, mascarpone cheese, and heavy cream.
2. Mix on low speed for 1 minute, then increase to high and whip until stiff peaks form (2-3 minutes). Be careful not to overmix.
3. If not using immediately, store in an airtight container in the refrigerator.

Step 3: Prepare the Berry Layers

1. In a small bowl, mix berry jam with 2 tablespoons of water to create a drizzle.
2. In another bowl, toss together the halved raspberries, blueberries, blackberries, and strawberries.

Step 4: Assemble the Waffle Cake

1. Place the first cooled waffle on a serving plate.
2. Drizzle a quarter of the berry jam mixture over the waffle.
3. Spread a generous layer of mascarpone cream frosting over the waffle.
4. Sprinkle ¼ cup of the mixed berries on top.
5. Repeat the layering process with the remaining waffles.
6. On the top layer, arrange whole berries for a decorative finish.

Step 5: Serve and Enjoy!

1. Serve immediately or refrigerate for up to 1 hour to maintain the best texture.
2. Slice, serve, and enjoy this light yet indulgent waffle cake!