Preheat your oven to 350˚F.
Melt 1/4 Cup of butter, mix it together with the brown sugar. Spread the mixture across the bottom of an 8" x 8" x 2" baking dish (In the video I use a 9x13). Add peaches on top of the mixture to cover the bottom of the baking dish.
In a medium bowl mix together flour, baking powder, and salt. In a second bowl bowl beat 1/2 Cup of softened butter for about 30 second to 1 minute. Beat in the sugar until combined, add eggs, and vanilla. Once combined alternate adding the flour mixture and milk.
Once completely combined pour over peaches in the baking dish. Place in the oven and make for about 45 to 50 minutes or until completely cooked.
Remove from the oven and allow to cool for about 5 minutes. Loosen cake along the sides and invert onto a serving platter.