Preheat oven to 350 °F degrees.
For the batter, melt butter and put 1 T. in a medium bowl for the filling. Combine the rest of the butter with the cassava flour, milk, 3 tbsp maple syrup, baking powder, and 2 eggs. Stir until smooth. Put half of the batter in a greased 8x10-inch casserole dish.
For the filling combine the remaining butter, the remaining maple syrup, the remaining egg, and the ricotta, and stir to combine.
Gently dollop the filling over the layer of batter. Gently spread the remaining batter over the filling with an offset spatula.
Bake for 45 minutes. Serve warm with allowed jam for brunch, or portion and freeze for later.