Ingredients:

  • 2 cups all-purpose flour
  • 3/4 cup granulated sugar
  • 1 tsp baking powder
  • 1/2 tsp baking soda
  • 1/2 tsp salt
  • 1 cup sour cream
  • 2 large eggs
  • 1/2 cup unsalted butter, melted and cooled
  • 1 tsp vanilla extract
  • 1 tbsp lemon zest
  • 2 cups fresh rhubarb, diced into 1/2 inch pieces
  • 1/2 cup chopped walnuts
  • 1/4 cup brown sugar
  • 2 tbsp all-purpose flour
  • 2 tbsp cold unsalted butter, cubed

Instructions:

  1. Preheat the oven to 350°F (175°C). Grease a 9x5 inch loaf pan and line it with parchment paper.
  2. Dice the fresh rhubarb into uniform 1/2 inch cubes and toss them in 1 tablespoon of the measured all-purpose flour until lightly coated.
  3. In a large bowl, whisk together the flour, granulated sugar, baking powder, baking soda, and salt.
  4. In a separate medium bowl, beat the eggs, then stir in the melted butter, sour cream, vanilla extract, and lemon zest until smooth.
  5. Pour the wet ingredients into the dry ingredients and stir with a spatula until just combined; do not overmix.
  6. Gently fold in the flour-coated rhubarb and chopped walnuts.
  7. Pour the batter into the prepared loaf pan.
  8. Prepare the streusel by pinching together the brown sugar, 2 tbsp flour, and cold cubed butter with fingers until crumbly, then sprinkle evenly over the batter.
  9. Bake for 60–65 minutes, or until a toothpick inserted into the center comes out clean or with a few moist crumbs.