In the jug of blender, add flour, milk, eggs, sugar, vanilla and salt. Blend on high speed until no lumps remain. The batter will be thin, smooth and frothy. Leave the batter in the blender jug to rest for 30 minutes to allow the flour to absorb the liquid and for it to come to room temperature.

Meanwhile preheat the oven to 425 degrees F. Place a rack on the middle rungs and ensure the rack above it is at least 7” to 8” above to allow room for the pancake to rise and puff up.

Place a 9” or 10” cast iron skillet in the oven while it preheats and leave it there for 20 - 30 minutes to get it really hot.

Just before proceeding with the next step, give the batter another whirl in the blender until frothy.

Take precautions for the next steps, the cast iron skillet will be very hot. Remove the skillet from the oven, add the butter and swirl the butter around to melt and coat the bottom and sides of the skillet. The butter will sizzle and turn into a golden brown butter which adds a toasty flavour and will help the pancake brown.

Pour the batter over the browned butter and it will sizzle and start cooking. Immediately return the skillet to the oven.

Bake for 12 minutes at 425 degrees F, then reduce heat to 375 degrees F and bake for an additional 8 - 10 minutes or until the pancake is puffed up, browned and crusty on the edges. Do not open the oven for the first 20 minutes of baking as this may cause the pancake to deflate before cooked.

Remove skillet from oven and let the puffed pancake settle for 5 minutes. It will deflate and create a unique wrinkled shape with crispy edges and a hollow cavity for the filling.

Meanwhile prepare the berries for garnish and arrange them in the cavity of the warm pancake. Dust the top and edges with icing sugar. Drizzle with maple syrup as desired. Serve warm or at room temperature.