In a large bowl, mix together melted butter, honey, flour, and active sourdough starter.
Cover and allow to ferment for 12 to 24 hours. (optional)
The next day preheat oven to 375 degrees. Line muffin tins with cupcake liners or grease well.
Add vanilla extract, baking soda, eggs, and salt to the batter.
Start mixing all the ingredients together in a stand mixer or hand mixer. Scrape sides occasionally.
Wash and dry blueberries. Place in bowl and dust with flour (optional).
Once the batter is mostly smooth without any large clumps, gently fold in the blueberries.
Spoon into muffin tins equally.
Bake for 20-25 minutes until tops start turning golden brown and a toothpick comes out clean.
Flip onto baking rack and allow to cool. A plate works well, too.