6tablespoonsunsalted buttercut into small cubes, plus more for the pan
Instructions
Make the filling
Prepare a bed of hot coals in a campfire.
Butter an 8-inch foil pan. Combine the strawberries, rhubarb, flour, sugar, and cinnamon in the pan and stir to mix well.
Stir the oats, flour, sugar, cinnamon, and salt together in a medium bowl. Spoon the oat filling over the fruit so that it covers it completely.
Scatter the butter cubes over the topping.
Cover the pan tightly with foil and cook over hot coals (not direct flame) until the top is golden and the filling is bubbling, 45 to 50 minutes.
Cool for at least 15 minutes before serving.
Notes
Get ahead--Mix your oat topping ingredients before heading out to camp. Store it in a resealable bag or container until you're ready to sprinkle it over the crisp.
Storage--Store leftover crisp in a sealed container at room temperature or in your cooler for up to 3 days.
Using cast-iron--You can also make this in a buttered 12-inch cast iron skillet. Cover tightly with foil while cooking.