Sheet Pan Apple Crisp

Preheat oven to 375°F. Lightly coat a large, rimmed baking sheet with butter. Microwave 4 tablespoons butter in a microwave-safe bowl on high until melted, 30 to 45 seconds.

Toss together apples and lemon juice on prepared baking sheet; drizzle with melted butter. Sprinkle with ½ cup sugar and ¼ teaspoon salt and toss until well combined and thoroughly coated. Spread mixture in an even layer.

Cut remaining 12 tablespoons butter into ½-inch pieces. Toss together oats, flour, cinnamon, cardamom, and remaining ½ cup sugar and ½ teaspoon salt in a large bowl until well combined.

Add butter pieces; using your fingertips, rub butter into oat mixture until moist clumps form and no dry bits of flour remain. Scatter evenly over apples on baking sheet.

Bake until topping is golden and crisp, 55 to 60 minutes. Let cool for at least 10 minutes. Scoop and serve with ice cream, if desired.