¼ teaspoon orange zest (optional; or ½ teaspoon lemon zest)
2 teaspoons vanilla extract
¾ cup Old Fashioned rolled oats
¾ cup all purpose flour (or almond flour for gluten-free)
½ cup brown sugar
½ teaspoon cinnamon
¼ teaspoon kosher salt
8 tablespoons cold salted butter (or coconut oil or vegan butter for vegan)
Direction :
Preheat the oven to 350 degrees Fahrenheit.
Make the filling: Chop the rhubarb into ½ inch pieces. Mix it with the granulated sugar, cornstarch, orange zest and vanilla extract in a bowl, then pour the filling into a round 9-inch pie pan, 9 x 9 inch baking dish or 7 x 11 baking dish.
Make the topping: In a medium bowl, mix together the oats, flour, sugar, cinnamon, and kosher salt. Cut the butter into small pieces and then use your hands to mix it into the oats until fully distributed and a crumbly dough forms. It may take a while so be patient; you can also use a fork or pastry cutter if you prefer. (If using coconut oil, it can be room temperature; use the same method to add it.) Pour the crumble on top and smooth it into an even layer with your fingers.
Bake: Bake for 45 to 50 minutes until the top is evenly golden brown and the filling is bubbly. Cool for 30 minutes to 1 hour, then serve warm. You can leave out your crisp on the counter for up to 1 day (covered, at night) so the crisp topping can stay crisp. After 1 day, refrigerate any leftovers. This crumble also freezes well for several months in a sealed container; reheat it in a 350 degree oven until bubbly and the topping is crisp.
