Preheat oven to 350 F. Butter a 9x13 inch baking dish. To this dish add the cubed peaches, brown sugar, vanilla, cinnamon, nutmeg, pinch of salt and the cornstarch. Stir well.
In a large bowl, combine flour, sugar, salt. baking powder and baking soda. Add the butter to the bowl. Using a pastry cutter, cut the butter into the dry ingredients until the mixture looks like a coarse crumbs with bits of butter here and there.
Add the heavy cream to the bowl. Stir everything until the ingredients are moistened and a sticky, chunky dough is formed.
Grab a portion of the dough, and with your palms flatten the dough before laying it over the peaches in the dish, Repeat with the remaining dough until the peaches are mostly covered, and the dough is all used up.
To make the egg wash, beat together egg and milk. Brush the top of the dough with egg wash. Bake at 350℉ for 50 minutes or until the pastry on top is golden and the filling is bubbly on the sides.
To serve, spoon a serving into a plate or bowl while it is still warm, then top with ice cream. Then enjoy, this little piece of heaven, my friends. And be glad for the leftovers!