Preheat oven to 325 degrees F. Line a baking sheet with parchment paper.

Combine crushed graham crackers, sugar, salt, and cinnamon (if using) in a medium bowl. Add melted

butter and vanilla (if using), and stir to fully coat the crumb mixture.

Spread crumbs onto the prepared baking sheet in an even layer. Bake for 8-12 minutes, until light

golden brown and fragrant. Watch the crumbles carefully so they don't burn (mine most often takes

around 10 minutes, but times will vary by oven and brand of graham crackers used). The graham

cracker mixture will be soft when you take it out of the oven and will crisp as it cools.

Cool the mixture to room temperature and break it up into crumbles. Store in an airtight container for

up to 3 days at room temperature, 1 week in the refrigerator, or 3 months in the freezer. Return to room

temperature before using the crumble to top your favorite sweet treats (such as parfaits, ice cream, or

yogurt).