In a stand mixer with the paddle attachment, cut the butter into the cake mix until crumbly. Then add ONE egg and mix until just combined. Reserve ½ cup of the crumble for the topping.
Grease a 9x13-inch pan and press the remaining crumble into the bottom of the pan. Bake at 350 degrees for 10 minutes.
Meanwhile, in a bowl with a hand mixer, beat together the cream cheese, sugar. Add ONE egg and the vanilla. Mix completely.
Drain peaches, cut into cubes, and distribute evenly over the top of the cooked crust. Dollop cheesecake batter over the peaches, filling in gaps, and spread slightly. Sprinkle with remaining crumble and bake again for 30 minutes or until crumble topping is browned and cheesecake is solid when the pan is shaken. (Test cheesecake batter with a toothpick, if needed. May take up to 45 minutes for glass/ceramic pans.)
Cool slightly, cut into squares, and serve with ice cream. Store leftovers covered in the refrigerator. Delicious cold or warm.