Blueberry Sourdough Muffins

0 Preheat the oven to 350 degrees F / 176 C. Line a 12 hole muffin tray with muffin liners.
1 In a small mixing bowl add the topping ingredients. Use a fork to combine to form a crumble. Set aside.
2 In a large mixing bowl mix together the flours, baking powder and soda, along with the sugar and salt. Whisk until well combined.
3 In a separate mixing bowl add the sourdough starter discard, 2 eggs, melted butter, lemon zest, vanilla extract and almond milk. Whisk until smooth.
4 Pour the wet ingredients into the dry ingredients, along with the fresh blueberries. Gently fold the mixture until combined. Do not over mix the batter.
5 Evenly divide the batter amongst 12 muffin liners. 
6 Sprinkle the prepared topping mixture over each of the cupcakes.
7 Place the muffins into the oven and bake for 20 minutes or until an inserted skewer comes out clean. 
8 Transfer to a cooling rack to cool completely before serving.