bakery-style almond rhubarb sour cream muffins

These bakery-style rhubarb almond sour cream muffins have been two years in the making thanks to rhubarb's annoyingly short season. That's two springs of recipe testing to bring you a tender, moist muffins studded with tart rhubarb pieces, flavored with almond extract, and topped with the most irresistible almond-oat crumble.