Heat oven to 425. Line a baking sheet w/ parchment paper. In bowl, combine flour, baking powder, and 1 tbsp sugar. In a cup, mix together buttermilk and vanilla.
Add buttermilk mix to the flour mix. Stir until just combined. Divide dough into 4 pieces and place on baking sheet. Brush tops w/ 1 tbsp buttermilk. Bake until golden brown, about 13 mins.
Spray a skillet w/ cooking spray, place over medium heat. Add peaches and cook 5-6 mins. Remove shortcakes from ove and let cool slightly. Slice each shortcake in 1/2. Top bottom w/ 1/4 of the peaches and 1/4 cup yogurt. Place top of shortcakes over peaches.