Ingredients:
- 2 cups (250g) all-purpose flour
- 3/4 cup (150g) granulated sugar
- 2 tsp (10g) baking powder
- 1/2 tsp (3g) baking soda
- 1/2 tsp (3g) salt
- 1 cup (240g) sour cream
- 1/2 cup (115g) unsalted butter, melted and cooled
- 2 large eggs
- 1 tsp (5ml) vanilla extract
- 2 cups (300g) fresh rhubarb, diced into 1/4-inch pieces
- 1/2 cup (65g) all-purpose flour
- 1/2 cup (100g) light brown sugar, packed
- 4 tbsp (55g) unsalted butter, cold and cubed
- 1 tsp (2g) ground cinnamon
Instructions:
- Wash the rhubarb stalks, trim the ends, and slice them into small, 1/4-inch cubes. Pat dry with a paper towel and toss with one tablespoon of the measured flour.
- Preheat the oven to 375°F (190°C).
- In a large bowl, whisk together the flour, granulated sugar, baking powder, baking soda, and salt.
- In a separate bowl, whisk together the sour cream, melted butter, eggs, and vanilla extract until smooth.
- Pour the wet mixture into the dry ingredients; stir with a spatula until just combined, leaving a few streaks of flour. Gently fold in the diced rhubarb.
- Fill each muffin liner about 2/3 full.
- In a small bowl, rub the cold butter into the flour, brown sugar, and cinnamon using fingers until the mixture resembles coarse wet sand.
- Sprinkle approximately 1 tablespoon of crumble evenly over each muffin.
- Bake for 18–22 minutes, or until the tops are mahogany-colored and a toothpick inserted into the center comes out clean.