- Preheat the oven to 350ºF. Grease a 9×13-inch pan with cooking spray; set aside.
- In the bowl of a mixer, combine the flour, sugar, and salt. Mix with the paddle attachment until combined. Cut the butter into small pieces and add in a few at a time. Mix until the butter is evenly combined and the mixture appears crumbly. (This can also be done by hand with a pastry cutter or with a fork.)
- Take out 1½ cups of the mixture and set aside. Press the remaining mixture into the prepared pan. Bake in the preheated oven until golden brown, 12 to 15 minutes. Let cool for at least 10 minutes.
- In a large bowl, whisk together the eggs and sugar. Add in the sour cream, flour and salt. Fold in the sliced peaches. Pour over the cooked crust. Take the remaining 1½ cups of the dry mixture and sprinkle over the top of the peaches. Bake until the top is lightly browned and the filling is set, 45 to 50 minutes. Cool at least 1 hour before cutting into bars. (I find that these slice much better after they have been refrigerated for a couple of hours.)
- Store in the refrigerator.