1. 1. Prepare Your Muffin Tin: Preheat your oven to 375 F (190 C). Line a 12-cup muffin tin with paper liners or grease it well with butter or non-stick spray. This ensures your muffins won’t stick.

2. 2. Combine Dry Ingredients: In a large bowl, whisk together the all-purpose flour, 1/2 cup granulated sugar, baking powder, 1/2 teaspoon ground cinnamon, and salt. Make sure there are no lumps and everything is evenly distributed.

3. 3. Mix Wet Ingredients: In a separate medium bowl, whisk together the sourdough discard, milk, melted butter, egg, and vanilla extract until well combined and smooth.

4. 4. Combine Wet and Dry: Pour the wet ingredient mixture into the dry ingredient mixture. Stir gently with a spoon or spatula until just combined. Be careful not to overmix; a few lumps are perfectly fine and will lead to tender muffins. Overmixing can result in tough muffins.

5. 5. Fill Muffin Cups and Bake: Divide the batter evenly among the 12 prepared muffin cups, filling each about two-thirds full. Bake for 15-18 minutes, or until a wooden skewer or toothpick inserted into the center of a muffin comes out clean. The tops should be lightly golden.

6. 6. Prepare the Cinnamon Sugar Coating: While the muffins are baking or cooling slightly, melt 1/4 cup of butter in a small bowl. In another small bowl, combine 1/2 cup granulated sugar and 1 teaspoon ground cinnamon.

7. 7. Coat the Warm Muffins: Once the muffins are baked, let them cool in the muffin tin for about 5 minutes. Then, carefully remove them from the tin. While still warm, dip the top of each muffin into the melted butter, allowing any excess to drip off. Immediately roll the buttered top in the cinnamon sugar mixture until fully coated. Serve warm and enjoy!