Cinnamon Rhubarb Muffins

Ingredients  (yields  20 standard muffins) 2 cups all-purpose flour 3/4 cup granulated sugar 2-1/2 tsp. baking powder 1 tsp. ground cinnamon 1/2 tsp. baking soda 1/2 tsp. kosher salt 1 cup sour cream 4 oz. unsalted butter, melted and cooled slightly 2 large eggs 1 tsp. pure vanilla extract 1-1/2 cups 1/4-inch-diced rhubarb For the…