Preheat oven to 350°F. Add parchment paper to the baking tray and grease it with butter/cooking spray. In a saucepan melt butter over medium heat until melted. Add the brown sugar. Bring it to a boil and remove it from heat. Pour into the bottom of the greased pan. Arrange the apples circularly over the brown sugar mixture

Sieve flour, baking powder, and salt 2-3 times and keep aside. In a large bowl, beat sugar and butter on medium speed until fluffy. Add eggs and vanilla and beat till the mixture becomes pale. Add milk and mix well

Add flour in small portions and gently mix without beating heavily. Add chopped apples and transfer the batter over the apple layer; spread evenly

Bake for 35-40 minutes or until a toothpick inserted in the center comes out clean. Cool for 10-15 minutes and invert gently. Run knife along the edges of the cake and flip upside down on a pan