1. Preheat the oven to 190C/380F/Gas 5 and line a 12-hole muffin tin with paper cases.
2. Mix the eggs, sugar, milk and melted butter in a large bowl. Sift the flour, baking powder, salt and cinnamon into the bowl. Stir well to combine.
3. Add the chopped apple and lightly mix.
4. Using half of the mixture, quarter-fill each of the muffin cases with the mixture and top with a few pieces of toffee. Cover with the remaining filling so the cases are half full.
5. Bake for 30-35 minutes until well risen and golden. Transfer to a wire rack to cool. Serve warm or cold.