Preheat oven to 180°C. Grease and line a 12-mould muffin tin.
For the topping, place ricotta, cream cheese, sugar and egg into the bowl of a food processor and process until smooth. Set aside.
For the muffin batter, place the macadamias, flour, sugar and baking powder into the bowl of a food processor and pulse until the mixture becomes a flour-like consistency. Do not over-process or the mixture will start to stick together - coarse macadamia pieces are fine.
Place the flour mixture into a large bowl.
In a separate bowl, lightly whisk together the eggs, butter, oil and milk. Add to the dry ingredients and stir to combine, taking care not to over-mix. Spoon into the lined muffin moulds so they are half full.
Spoon heaped tablespoons of the ricotta mix over the muffin batter and arrange approximately five berries on top of the ricotta mixture.
Bake for 15-20 minutes until the muffins are puffed and golden and a skewer inserted into the centre of one comes out clean. Cool in the tin for 10 minutes.Run a butter knife around the edge of each muffin and gently lift the muffin out onto a wire rack to cool.