Nutrition per serving may change if servings are adjusted.
1¾ cups regular rolled oats, divided
¾ cup whole-wheat pastry flour or whole-wheat flour
½ cup all-purpose flour
½ cup packed brown sugar (see Tip)
1 teaspoon baking powder
½ teaspoon baking soda
¼ teaspoon salt
¾ cup buttermilk
½ cup refrigerated or frozen egg product, thawed, or 2 eggs, lightly beaten
2 tablespoons canola oil
1 teaspoon vanilla
1 cup finely chopped rhubarb
1 tablespoon packed brown sugar (see Tip)
½ teaspoon ground cinnamon
¼ cup chopped walnuts
Preheat oven to 350°F. Line twelve 2½-inch muffin cups with paper bake cups; coat paper cups with cooking spray. Or, coat muffin cups with cooking spray.
Place ¾ cup of the oats in a food processor; cover and process until ground. Transfer to a large bowl. Stir in another ¾ cup of the oats, both flours, the ½ cup brown sugar, baking powder, baking soda, and salt. Make a well in center of the flour mixture.
Combine buttermilk, egg, oil, and vanilla in a medium bowl. Stir in rhubarb. Add the rhubarb mixture all at once to the flour mixture; stir just until moistened (batter should be slightly lumpy). Spoon into the prepared muffin cups, filling each about three-fourths full.
For streusel topping, stir together the 1 tablespoon brown sugar (see Tip) and the cinnamon in a small bowl. Stir in the remaining ¼ cup oats and the walnuts. Sprinkle over the batter in the muffin cups.
Bake 20 to 22 minutes or until a toothpick comes out clean. Cool in the muffin cups on a wire rack for 5 minutes. Remove from the muffin cups. Serve warm.
Tip: If using a sugar substitute for the muffins, we recommend Splenda Brown Sugar Blend. Follow package directions to use product amount equivalent to ½ cup. Nutrition Per Serving with Substitute: same as below, except 166 cal, 25 g carb. (6 g sugars). We do not recommend using a sugar substitute for the streusel topping.