2½ cups self-rising flour, divided
7 Tbs. salted butter, divided
1/3 cup plus 2 Tbs. granulated sugar
1 tsp. plus a splash of pure vanilla extract
1/3 to 1/2 cup whole milk
3 cups mixed berries (cut strawberries, raspberries, blueberries, and blackberries recommended)
1 Tbs. turbinado sugar
Preheat the oven to 400°F.
Place two cups of the flour in a large bowl.
Cut six tablespoons of the butter into small cubes. Using a pastry blender or two knives, cut the butter into the flour until the mixture looks like grated Parmesan cheese. Mix in the sugar and cinnamon.
In a separate bowl, whisk the vanilla into 1/3 cup of the milk. Make a well in the center of the dough, pour in the milk, and combine. The dough should be wet and sticky; you may use up to a half cup of milk if necessary.
Dust the dough, rolling pin, two-inch biscuit cutter, and a sheet of parchment paper very liberally with the remaining flour.
Dump the dough onto floured parchment paper and roll it out to a 1/2-inch-thick round. Starting from the outside edge of the dough, use the floured biscuit cutter to cut straight down into the dough, making five or six small biscuits about two inches apart.
Place the parchment paper with the dough onto a rimmed baking sheet. Remove the cut-out biscuits from the centered dough round and line them up along the edge of the sheet. (It’s okay for the biscuits to touch each other.) Fill the holes in the dough with heaping servings of berries.
Melt the remaining tablespoon of butter and brush it on the biscuits and the dough round with the holes. Sprinkle all with turbinado sugar. Bake the berry-filled dough and biscuits for 16 to 18 minutes, turning the sheet halfway through, until the biscuit tops are a light golden brown.
To serve, slice the berry-filled round into pie-like wedges. Top each slice with whipped cream or ice cream, if desired. You may serve each portion with a biscuit, or save the cutout biscuits for later.