Make the Peach Filling:

• Gently toss the peaches, sugar, and lemon juice in a large bowl. Let sit for 1 hour to allow maceration.
• While peaches are macerating make the Streusel Topping. In a medium bowl, combine the flour, brown sugar, pecans, oats, cookie crumbs, cinnamon and salt. Using a fork or pastry cutter, cut the softened butter into the dry ingredients. Once halfway incorporated, use your hands to squeeze the ingredients together, until a moist crumb forms; set aside.
• Preheat the oven to 350ºF, and spray an 8-inch baking dish with nonstick cooking spray.
• Pour macerated peaches into a colander set over a bowl to thoroughly drain the juice. You should have about 3/4 cup juice. Place the juice into a small saucepan and cook over medium-high heat until reduced by half, about 7-10 minutes. Add the reduced juice, cornstarch, vanilla, cinnamon, and salt to the peaches, gently stirring to coat. Pour the filling into the baking dish.
• Evenly crumble the streusel topping over the peach filling. Bake for 35-40 minutes, or until bubbly and golden brown on top.
• Allow the crisp to cool for at least 30 minutes before serving. Leftover crisp can be stored covered in the refrigerator for up to 5 days.