4 cups peach slices, with or without skin (or blueberries or pitted cherries)
2 Tbsp lemon juice
1/3 cup sugar, brown or white
2 1/2 Tbsp cornstarch
1/4 tsp cinnamon (optional)
1 cup flour
3 Tbsp sugar
1 tsp baking powder
1/2 tsp baking soda
1/4 tsp salt
3 Tbsp cold butter
2/3 cup buttermilk (or milk + 2 tsp vinegar or lemon juice)
Toss the peaches with the lemon juice and put them in a 7" baking pan or casserole. A cheesecake pan will NOT work for this. Mix the sugar, cornstarch, and cinnamon and toss with the peaches.
Put 1 1/2 cups of water in the Instant Pot and put the peaches on the trivet. Close the pot and push Pressure Cook (or Manual) and adjust the time using the + or - button to get to 30 minutes.
While the peaches are cooking, make the biscuit topping. Whisk the dry ingredients together. Use a pastry blender or food processor to cut in the cold butter until it is the size of small peas. By hand, add the buttermilk or soured milk and combine with a few swift strokes.
When the Instant Pot beeps that it's done, flip the valve to Venting and when the pin drops, press Cancel and open the pot.
Drop small spoonfuls of the biscuit mix over the peach mixture. Close the pot, set the valve back to Sealing, and reset the time for 15 minutes. When it beeps that it's done, leave it for 5 minutes natural release. Flip the valve to Venting and when the pin drops, remove the cobbler. Brown under a preheated broiler for a few minutes, if desired.