Preheat the oven. Preheat oven to 350 degrees F. and set oven rack to the center position.
Prepare baking dish. Butter or spray an 8x8 baking dish with non-stick cooking spray. Set aside.
Mix apples. Transfer the peeled, cored, and sliced apples to a large mixing bowl. Add the granulated sugar, brown sugar, cinnamon, salt, lemon juice, and lemon zest. Mix well to combine.
Saute the apples. Add the butter to a large skillet over medium-high heat. Add the apples and mix well to combine in the butter. Cook the apples, stirring gently (yet often) until the apples are just starting to soften. Remove from heat and transfer to your prepared baking dish.
Prepare the crisp topping. In a medium mixing bowl mix together the flour, oats, ground cinnamon, salt, and chopped pecans (if using). Cut the butter into small cubes and add them to the bowl. Use your fingers to gently press the butter into the flour and oat mixture. Continue to mix and press and break into smaller pieces until the mixture resembles little crumbs the size of peas.
Spread crisp topping over the apples. Transfer the crisp topping to the baking dish with the apples. Spread evenly over the top of the apples.
Bake. Transfer the baking dish to the oven and bake for approximately 25-35 minutes.
Serve. Remove from the oven and set aside to cool for 5-10 minutes before serving with your favorite ice cream, caramel sauce, or whipped cream. Enjoy!
We will be sauteeing the apples first before we bake them. It ensures that all the apples get fully cooked, but most importantly, it allows us to cut the apples into slightly thicker slices. Not crazy thick, but thick enough that, when all is said and done, we can taste that I'm actually biting through an apple.
Note- do not cook the apples until they are completely soft and mushy. You want them to start softening and release some of their juices.