Place a rack in the middle of the oven and preheat it to 190 °C / 375 °F (fan-assisted oven).
make the dough
Add all-purpose flour, whole wheat flour, sugar, a pinch of salt, and baking powder to a bowl. Stir to combine and add the grated cold butter. Rub the mixture with your fingers until you get a sand-like texture. In a separate bowl, beat together milk and egg. Pour into the dry mixture and stir with a spatula to combine. Place in the fridge for 10 minutes.TipFeel free to use a food processor for this step.
Clean the peaches, remove the kernel, and cut them into wedges. Place the peaches in a deep baking dish (approx. 20 cm x 30 cm or 8-inch x 12-inch in size). Add the cornstarch, brown sugar, and vanilla paste. Stir to combine.
cut the dough
Lightly dust the working surface and place the dough on top. Roll the dough to 1 cm (1/2-inch) thickness and the size of your baking dish. Cut out circles and put them on top of the peaches in the baking dish. Brush the biscuits with melted butter and sprinkle with sugar.
Place the Peach Cobbler with Whole Wheat Flour in the preheated oven. Bake for 45 - 50 minutes at 190 °C / 375 °F (fan-assisted oven). If the cobbler is getting brown too quickly, cover it with aluminum foil for the last 15 minutes of baking. Take the baked Peach Cobbler from the oven and set aside for a few minutes, then divide between six bowls and serve with vanilla ice cream.