Heat oven to 200C/fan 180C/gas 6. Line a 12-hole deep muffin tin with paper cases. Tip the flour, baking powder, cinnamon and a pinch of salt into a large bowl, then stir in the sugar. Mix together the milk, eggs and melted butter in a large jug and pour into the dry mix all at once, along with the pears and a third of the toffee pieces. Stir briefly until just beginning to combine - the batter should still be quite lumpy and have streaks of flour.
Divide the mixture between the cases, then sprinkle with the remaining toffee and the flaked almonds. Bake for 25-30 mins until the muffins are risen, golden and feel firm when pressed (the molten toffee will be extremely hot so be careful not to touch it). Remove from the tin to a wire rack to cool.