Ingredients:

  • 1/2 cup (65g) all-purpose flour
  • 1/3 cup (65g) granulated sugar
  • 4 tbsp (56g) unsalted butter, cold and cubed
  • 1/2 tsp ground cinnamon
  • 2 cups (250g) all-purpose flour
  • 3/4 cup (150g) brown sugar, packed
  • 1 tsp baking powder
  • 1/2 tsp baking soda
  • 1/2 tsp sea salt
  • 1 large egg, room temperature
  • 1 cup (240g) full-fat sour cream
  • 1/3 cup (80ml) vegetable oil
  • 1 tsp vanilla extract
  • 1.5 cups (225g) fresh rhubarb, diced 1/4 inch

Instructions:

  1. In a small bowl, combine 1/2 cup flour, granulated sugar, and cinnamon. Rub the cold, cubed butter into the mixture using your fingers or a fork until it resembles coarse, clumpy sand. Place in the refrigerator until ready to use.
  2. Preheat your oven to 400°F (200°C) and line a 12-cup standard muffin tin with paper liners.
  3. In a large mixing bowl, whisk together 2 cups flour, brown sugar, baking powder, baking soda, and sea salt, ensuring no large brown sugar lumps remain.
  4. In a separate medium bowl, whisk the egg, sour cream, vegetable oil, and vanilla extract until completely smooth.
  5. Pour the wet ingredients into the dry ingredients. Use a silicone spatula to fold the mixture until just combined; a few small streaks of flour are acceptable.
  6. Gently fold in the diced rhubarb. Divide the batter evenly among the 12 muffin cups.
  7. Generously top each muffin with the chilled streusel mixture. Bake for 22 minutes or until a toothpick inserted into the center comes out clean. Cool on a wire rack.