Preheat the oven to 350° F and coat an 8×8 pan with non-stick spray. Set aside.
Add ⅓ butter to a large saute pan set over medium heat. Let butter melt and turn slightly golden brown.
Add diced zucchini, 1 teaspoon cinnamon, ½ tablespoon apple pie spice, nutmeg, ¼ cup sweetener, and lemon juice to the pan. Toss and cook for 5-7 minutes until zucchini is slightly tender. Remove from heat and add to your prepared pan.
Add almond flour, nuts, ⅓ cup butter, and remaining sweetener to a small bowl. Mix well with a fork to a crumble consistency. Pour mixture over zucchini.
Bake for 25-30 minutes until the crumble is golden brown and zucchini mixture is bubbling.
Serve with keto friendly ice cream or whipped cream if desired.