Topping
3/4 cup all purpose flour
3/4 cup old fashioned oats
1/2 cup (packed) golden brown sugar
1/2 teaspoon ground cinnamon
1/4 teaspoon fine sea salt
1/2 cup (1 stick) chilled unsalted butter, cut into 1/2 inch cubes
3/4 cup chopped walnuts (about 3 ½ ounces)
Filling
3/4 cup sugar
2 tablespoons cornstarch
1/4 teaspoon ground cinnamon
Pinch of fine sea salt
pounds apricots (about 12 large), halved, pitted, cut into 1/2 inch cubes (about 6 cups)
Vanilla Ice Cream

For topping: Mix flour, oats, brown sugar, cinnamon, and salt in medium bowl. Add butter and rub in with fingertips until mixture comes together in moist clumps. Stir in walnuts.

Do ahead: Can be made 1 day ahead. Cover and chill.

For filling: Position rack in center of oven and preheat to 350°F. Mix sugar, cornstarch, cinnamon, and salt in large bowl. Add apricots and toss to coat. Transfer apricot mixture to 11x7x2-inch glass baking dish. Sprinkle topping over.

Bake crisp until filling is bubbling around edges and topping is crisp and golden, about 1 hour. Cool at least 20 minutes. Serve warm with ice cream.

6 to 8 Servings