1-First Step: Prepare the streusel topping Combine 1/4 cup flour, 2 tbsp sugar, and 2 tbsp cold cubed butter in a bowl. Use fingers to rub until crumbly pea-sized pieces form. Set aside in fridge to stay cold. This adds the signature bakery muffin top crunch.

2-Second Step: Mix dry ingredients Whisk 2 1/4 cups flour, 1 tsp baking soda, 1 tsp baking powder, and 1/2 tsp salt in a medium bowl. Spoon flour into measuring cup and level to avoid dense cookies. This ensures even rising.

3-Third Step: Cream butter and sugars Beat 1 cup softened butter, 3/4 cup granulated sugar, and 1/4 cup brown sugar on medium speed 2-3 minutes until light and fluffy. Scrape bowl sides. Creaming traps air for soft texture.

4-Fourth Step: Add wet ingredients Mix in 2 eggs one at a time, then 2 tsp vanilla. Beat in 1/2 cup buttermilk until smooth. Dough may look curdled; it will combine later. Use room-temp ingredients for best emulsion.

5-Fifth Step: Combine wet and dry Gently fold dry mix into wet with spatula until just combined. Avoid overmixing to keep cookies tender. Dough will be thick like muffin batter.

6-Sixth Step: Fold in blueberries Toss 1 1/2 cups blueberries in 1 tbsp flour. Fold into dough carefully to avoid bursting. Frozen work well; pat dry first. Distribute evenly for every cookie burst.

7-Seventh Step: Chill dough Cover and chill 30 minutes. Chilling prevents spreading for thick muffin cookies. Scoop 2-tbsp portions meanwhile.

8-Eighth Step: Preheat and prep sheets Heat oven to 350°F. Line sheets with parchment. Space scoops 2 inches apart. Press streusel on tops lightly.

9-Ninth Step: Bake Bake 12-15 minutes until edges golden, centers soft. Rotate halfway. Cool on sheet 5 minutes, then rack. They firm as they cool.

10-Final Step: Finishing touches and serving Drizzle optional glaze (1 cup powdered sugar + 1 tbsp milk). Serve warm or store. Pair with coffee for breakfast bliss.