Blueberry-Nectarine (or other) Fruit Crisp

Ingredients

• Preheat oven to 350°F.
• Allow the crisp to cool for 20 minutes, then serve with whipped cream or ice cream if desired.
• 2 cups rolled oats
• 1 cup flour
• 1/2 cup almond flour
• 3/4 cup firmly packed dark brown sugar
• Zest and juice of 1 lemon
• 1/2 teaspoon kosher salt, plus more if needed
• 12 tablespoons (1-1/2 sticks) cold, unsalted butter, cut into 12 pieces
• 6 cups fresh blueberries
• 2 tablespoons cane sugar, or more to taste
• 2 tablespoons cornstarch or instant tapioca
• 6 nectarines, sliced into wedges (should yield 4-6 cups sliced)
• Whipped cream or vanilla bean ice cream, optional