1. Preheat an oven to 400 degrees.

2. Using a stand mixer, beat cream cheese and 1/4 c. butter until well combined. Add egg, milk, and vanilla. Mix until combined, but with the cream cheese still chunky.

3. In a large bowl, combine 1 3/4 c. flour, 1/2 c. sugar, 1/4 c. brown sugar, baking powder, and salt. Make a well in the mixture and add the cream cheese mixture. Stir until just combined.

4. In a small bowl, combine blueberries, 1 Tbsp. flour, and 1 Tbsp. sugar. Add blueberries to batter, gently folding in.

5. Add liners to jumbo muffin pans and fill each cup until mostly full.

6. In a small bowl, combine cake mix and 1 Tbsp. butter with a fork, until crumbly. Sprinkle mixture evenly across muffins.

7. Bake for about 25 minutes, until muffins are golden and a toothpick comes out clean.

8. Let cool in pans for 5 minutes, then remove from pans and let cool on racks.