1. In a large bowl, mix flour, baking powder and baking soda. Add the butter and use a pastry cutter to cut the butter into the flour until the pieces are even and about the size of peas.
2. Stir in the beaten eggs until combined. Stir in 1½ cups buttermilk until the dough comes together and is sticky. If it is too dry, add more buttermilk 1 tablespoon at a time, mixing after each addition, until it reaches the correct consistency.
3. Position a rack in the middle of the oven and preheat the oven to 400°F. Line a baking sheet with parchment paper.
4. Use a large ice cream scooper to scoop mounds of dough onto parchment paper lined cookie sheet.
5. Arrange them so that they are not touching.
6. In a small dish, beat together the remaining egg and 1 tablespoon buttermilk. Brush the mixture on the top of the biscuits. Sprinkle with coarse sugar
7. Bake until golden brown, 15 to 20 minutes. Let cool slightly in the pan on a rack.
Strawberry Mixture
Mix sliced strawberries with sugar well. Place in refrigerator until juices form.
Whipped Cream
Using a stand mixer fitted with a whisk attachment, whip the heavy cream, sugar, and vanilla extract on medium-high speed until medium peaks form, about 3-4 minutes. Medium peaks are between soft/loose peaks and stiff peaks and are the perfect consistency for topping.
