Preheat oven to 350° F. Grease a shortcake pan. (I bought mine off Amazon, but they are available in large kitchen stores too)
In the bowl of a mixer, beat the eggs for 4 minutes with the whisk attachment. Slowly add in sugar, a little at a time; beat until light and fluffy, 4 to 5 minutes.
In a separate bowl, whisk together the flour and baking powder, and add to egg mixture until just combined.
In a saucepan, heat ½ cup milk and 2 tablespoons butter until butter is melted.
Pour into the batter a little at a time, mixing constantly with whisk attachment (this is important for the air and the leavening). Add vanilla extract.
Pour into prepared shortcake pan.
Bake in preheated oven until cakes are golden color and a toothpick inserted in the center of them comes out clean, approx 15-20 minutes. Remove from oven and let sit 5 minutes before removing from pan. Cool completely on cooling rack.
For Raspberry Sauce:
Place raspberries, sugar and lemon in a small saucepan on the stove over medium heat. In a small bowl, dissolve the cornstarch in the cold water and mix well, then add to the pot.
Cook the whole mixture for 10-15 minutes, over medium heat and stir occasionally until raspberries are soft, juicy and you see the mixture thicken. Set aside to cool. Refrigerate for up to a week in an airtight container.
For Whipped Cream:
In a bowl, pour in the heavy whipping cream, the vanilla extract and the sugar. Mix on low until you start to see some foam. Turn it up a notch and continue. Gradually turn it up a little at a time until you see the whipped cream start forming soft peaks. At this point, you will need to start watching carefully - you're aim is stiff peaks but it's VERY easy to over whip.
Once it's ready, it can be used immediately, or It can be stored in an airtight container in the refrigerator for about 2-3 days.
To Assemble Raspberry Shortcake Double Stacks:
One Shortcake, topped with whipped cream and then raspberry filling.
Top with a second shortcake and repeat. Sprinkle raspberries on top and on the plate. Serve!