Nectarines or peaches play so nicely with the warm flavor of brown sugar in this simple sheet cake. Add a little browned butter glaze for an out of this world flavor combination!
Preheat the oven to 375°F and grease a 13x18x1-inch half sheet cake pan.
Wash peaches and thinly slice or dice.
In a bowl, toss peach slices/cubes with corn starch and cinnamon. Set aside.
In a large saucepan over medium heat, bring butter, sugars, and water to a boil. Remove from heat.
Whisk in remaining ingredients until just combined. Spread in prepared pan.
Arrange sliced peaches over cake batter.
Bake for 25-30 minutes or until cake is done (the cake will bake darker than you are used to due to the brown sugar. Test the cake and don't go by color.)
Cool most of the way and then drizzle with brown butter glaze, or dust with powdered sugar.
Notes
You can make half of the recipe in a 9x13-inch pan. Just use the button above the ingredients to adjust the amounts accordingly.