Pour all AP flour, baking powder, baking soda, cinnamon (or seasoning), and salt into mixer. Mix up till combined.
Pour sourdough discard, melted butter, extract, sugar, and eggs into mixer. Mix till JUST combined.
Add in the fruit. Mix till JUST COMBINED. Over mixing will make tough muffins. Fill jumbo muffin liners or regular muffin liners 2/3 full.
If you're doing crumb topping, add the rest of the ingredients to your now empty mixer bowl: flour, brown sugar, and butter. Mix till crumbly. Add evenly across all muffins.
Do a 15-30 minute batter rest. Bake 425° for 8 mins, and then bake at 350° for 15-20 mins or until the muffins are 200° internal temp. ENJOY!
Notes
You can make this into micro muffins, mini muffins, jumbo muffins, or mini breads. Literally the same recipe.