Lemon Poppy Seed Muffins

1. Preheat oven: Preheat oven to 400ºF and grease or line a standard 12-cup muffin pan.
2. Mix the dry ingredients: In a medium mixing bowl, whisk together the flour, poppy seeds, baking powder, baking soda, and salt.
3. Mix the wet ingredients: In the bowl of a stand mixer fitted with the paddle attachment (or using a bowl and handheld electric mixer), cream together the sugar, butter, and lemon zest, scraping down the bowl and beater as needed. Beat in eggs one at a time, until fully incorporated, again scraping down as needed. Beat in the sour cream, lemon juice, and vanilla until smoothly incorporated.
4. Combine: Add the dry ingredients to the wet and mix in on lowest speed until mostly incorporated. Finish folding together by hand just until all ingredients are evenly combined - the batter will be thick.
5. Fill the muffin tin: Divide batter evenly between the prepared muffin cups (note they will be very full and mounded in centers). Smooth out tops with a fingertip if needed.
6. Bake: Bake muffins at 400ºF for 10 minutes, and then reduce heat to 350ºF and bake another 7-10 minutes, until a toothpick inserted in the center of a muffin comes out clean. Cool muffins in pan for about 10 minutes, and then transfer to a wire rack to cool completely before glazing.

Lemon Glaze

1. Prep the glaze: Combine confectioner's sugar, melted butter, lemon juice, and lemon zest in a small mixing bowl and whisk together until smooth. The glaze should be thick and opaque, but still fluid - add more confectioner's sugar or lemon juice as needed to achieve the correct consistency.
2. Drizzle: Spoon glaze onto muffins and allow to drizzle down sides. Let set before serving. Muffins can be stored in an airtight container, and should be kept refrigerated if glazed.