3:2:1:1 (oats : flour : sugar : liquid fat)
Mix in a bowl till well combined.
Spread it out in a single layer on a parchment lined rimmed baking sheet.
Pop in the freezer for about an hour.
Scoop the crumbly frozen mix into a ziptop bag for ease.
Notes:
*You can also batch mix the dry ingredients and add the fat to each individual batch when needed.
Fruit:
Fruit formula:
1c fruit : ½ tsp lemon juice : 1 tsp thickener : 1 tbl sugar
https://www.allrecipes.com/article/how-to-make-fruit-crisp/#:~:text=Topping%20formula:%20Your%20basic%20crisp,and%201%20cup%20liquid%20fat.