For the sponge:
1 cup sourdough starter
2 cups sour cream
4 cups flour
I like to do 2 cups all purpose and two cups soft white wheat flour lightly sifted to get the bigger pieces of bran out.
1 cup milk

Mix up all the ingredients for the sponge the night before you want to make your muffins and let sit on the counter.

For the muffins:
1 cup softened butter
1 cup coconut sugar
4 eggs
2 Tbs vanilla
1 tsp salt
2 tsp baking soda
1 1/2 cups blueberries

Cream the butter and sugar together until soft and fluffy. Then add the eggs and vanilla and mix until smooth. Mix in the salt and baking soda and then add the sponge ingredients. This can be tricky to mix in so I like to mix it for about a minute, scrap the sides down, and keep going. Be careful not to over mix.

Fill your muffin liners with the batter. For tall, bakery style muffins use parchment paper. Simply cut them into 5x5 squares and use a small can to shape them. The longer sides will keep the edges of the muffins from spreading.

To add the blueberries I like to sprinkle them on top and use a butter knife to press them down. This will help keep them from sinking to the bottom of the muffin.

For the streusel:
1 cup flour
1/2 cup coconut sugar
1/4 tsp cinnamon
1/8 tsp salt
1/2 cup butter
Pecans crushed into small pieces

Use a pastry blender to mix until the butter is about pea size and everything is incorporated. After you add the blueberries, generously top all the muffins with the streusel topping.

Here’s another tip for fluffy muffins!
Preheat your oven to 425° and bake the muffins for five minutes. After the five minutes turn the oven down to 350° leaving the muffins in the oven, and bake for an additional 15-18 minutes. The higher temperature will help the muffins raise faster and not spread out.

ENJOY!!

Note:
The muffin batter is lightly sweet because the streusel will add more sweetness and balance the muffins out. For a sweeter muffin increase sugar by 1/4-1/2 cup.