Preheat oven to 375 degrees F.
If using cake flour sift into a large mixing bowl, if using all-purpose flour just add to bowl (no sifting is necessary). Add 3/4 cup sugar, baking powder, baking soda, and salt and whisk to combined.
Mix vanilla with buttermilk then pour buttermilk mixture into well in flour and fold and stir with a spoon just until combined (don't over-mix, it should be lumpy).
Dollop and just lightly spread spoonfuls of the mixture evenly over top of peaches (about 12 dollops across the top).
Whisk together remaining 2 tsp sugar with 1/4 tsp cinnamon and sprinkle evenly over top.
Bake in preheated oven until topping is golden brown and set and and filling is bubbling, about 40 - 45 minutes.
Remove from oven and let cool several minutes before scooping into bowls. Serve with vanilla ice cream.
*Recipe originally listed as using 3/4 cup cake flour and 3/4 cup all-purpose flour, now I either use all of one or the other. Cake flour offers a fluffier softer topping while all-purpose flour is a bit more dense.