Step 1

Preheat oven to 425°F (218°C). Spray a 12-count muffin pan with nonstick spray or line with cupcake liners. Set aside.

Step 2

In a large bowl, toss the flour, poppy seeds, baking soda, baking powder, and salt together. Set aside.

Step 3

In a large bowl using a handheld or stand mixer fitted with a paddle attachment, beat the butter on high speed until smooth and creamy, about 1 minute. Add the granulated sugar and beat on high until creamed, about 2 full minutes. Scrape down the sides and bottom of the bowl as needed. Add the eggs, yogurt, and vanilla extract. Beat on medium speed for 1 minute, then turn up to high speed until the mixture is combined and creamy. Scrape down the sides and bottom of the bowl as needed.

Step 4

Pour the dry ingredients into the wet ingredients and beat on low speed until just about combined. Add the milk, lemon juice, and lemon zest and continue to beat on low until combined. Fold in the blackberries with a wooden spoon or rubber spatula. They may bleed a little, so be careful!

Step 5

Spoon the batter evenly into each cup or liner, filling each all the way to the top. Bake the muffins for 5 minutes at 425°F (218°C) then, keeping the muffins in the oven, reduce the oven temperature to 350°F (177°C). Bake for an additional 15-18 minutes or until a toothpick inserted in the center comes out clean. The total time these muffins take in the oven is about 22-23 minutes, give or take. Allow the muffins to cool for 10 minutes in the muffin pan, then transfer to a wire rack and drizzle with glaze. Muffins stay fresh stored in the refrigerator for 1 week.

Step 6

Whisk the confectioners’ sugar and lemon juice together. Drizzle over muffins.