1/4 cup unsalted butter
3/4 cup (packed) light brown sugar
2 teaspoons honey
2 cups (about 9 ounces trimmed) fresh rhubarb (cut into 1/2-inch pieces)
2 large eggs (at room temperature)
2/3 cup Sugar
1/3 cup sour cream (at room temperature)
1 teaspoon vanilla extract
1/2 cup unsalted butter (melted and cooled)
1 1/4 cups unbleached all-purpose flour
3/4 teaspoon baking powder
1/4 teaspoon baking soda
1/4 teaspoon salt