Banana, yoghurt, honey, oats and walnut muffins

It's my Saturday morning baking session and so I've used up a couple of ripe bananas to make some breakfast muffins.  These fill the house with an amazing smell while they're cooking, and taste delicious!

Ingredients

2 eggs

2 ripe bananas, mashed

2 ½ oz butter, melted (plus extra for greasing)

4 fl.oz (125ml) natural yoghurt

2 tbsp honey

1 tsp vanilla essence

3oz demerara sugar

2 tbsp porridge oats

2 tbsp ground walnuts

10oz self-raising flour

1 tsp baking powder

½ tsp bicarbonate of soda

1 tsp ground cinnamon

For the topping

2oz plain flour

2 oz butter, cubed and at room temperature

2 tbsp demerara sugar

1 tbsp porridge oats

1 tbsp ground walnuts

Method

1. Preheat oven to 180°C. Grease 24 silicon cupcake cases or 12 muffin cases, or line with paper cases.
2. In a large mixing bowl, lightly beat the eggs and add the mashed banana, melted butter, yoghurt, honey and vanilla. Whisk until well combined.
3. Add the sugar, oats and ground walnuts and beat well.
4. Sift in the flour, baking powder, bicarbonate of soda and cinnamon, and stir until just combined (do not overmix).
5. Spoon the mixture into muffin cases.
6. In a medium bowl, make the topping by rubbing the butter into the flour with your fingertips until it resembles fine breadcrumbs.
7. Add the sugar, oats and ground walnuts and mix with your fingertips until well combined.
8. Sprinkle the topping over the muffins.
9. Bake for 20 minutes or until cooked through when tested with a skewer.
10. Cool in the cases for 5 minutes, then turn onto a wire rack to cool completely.