This recipe comes from barbeque guru Steven Raichlen, who taught us that delicious desserts can indeed be cooked on a grill. In this case, the faintest scent of smoke gives blueberry crumble a spicy flavor. If you’d rather make it in your oven, though, simply bake at 375° until the topping browns and the berries are bubbling, 40–50 minutes. And forget about the wood chips.
Place blueberries in a nonreactive mixing bowl. Add ¼ cup flour, sugar, lemon zest, and lemon juice; then toss gently to mix. Spray an 8x10-inch foil pan or oval ceramic baking dish lightly with cooking oil and spoon in mixture.
Put gingersnaps, brown sugar, and remaining ½ cup flour into a food processor and process until a coarse powder forms. Add butter and salt; then pulse until crumbly. Spoon topping over blueberry mixture.
Set up your grill for indirect cooking (coals arranged to one side, away from the dish) and preheat to medium-high. If you’re using a gas grill, put all of the wood chips in the smoker box and run the grill on high until you see smoke; then reduce heat to medium-high. If you’re using a charcoal grill, preheat it to medium-high, then toss all the wood chips or chunks on the coals.
Place pan in center of hot grate, away from heat, and cover grill. Cook until blueberry mixture is bubbling and topping browns, about 40 minutes. (Keep the temperature steady; if you’re using a charcoal grill, add a small scoop of extra coals about midway through.) Serve with vanilla ice cream.