Preheat oven to 425 degrees F.

Set out a deep, round, nonstick cake pan 8+1/2"

Beat together 4 tablespoons of butter, brown sugar and pinches of nutmeg and cardamom until smooth and creamy.

Use a spatula to spread the mixture evenly into the bottom of the pan.

Zest one of the oranges and set aside the zest.

Peel both oranges, both the outer peel and the white pith and dice the fruit into small chunks. Capture and reserve any runoff juice and add it to the batter.

Spread the orange chunks evenly into the pan on top of the brown sugar mixture.

In a large mixing bowl, beat the remaining butter and the white sugar until smooth and creamy.

Beat in the eggs one at a time, beating briefly after each addition until blended.

Beat in the vanilla and reserved zest.

In a small mixing bowl stir the baking powder, salt, nutmeg, and cardamom into the flour.

Beat the flour into the batter in three additions alternating with the milk in two additions.

Pour the batter into the cake pan over the oranges.

Bake for 35 minutes, covering loosely with aluminum foil after 20-25 minutes when the cake is browned.

The cake is done when the center is set and firm and a tester inserted comes out clean.

Remove from the oven and cool on a wire rack for 10 minutes.

Slide the blade of a knife around the edges of the cake to loosen, place a serving platter or a cake plate upside down on top of the cake pan and flip the cake onto the platter, the caramel and oranges side up; gently lift the pan.