Make Ahead: Yes, this recipe is perfect to make ahead. Just allow to cool completely then store in the fridge. Leftovers: Allow to cool then place in an airtight container, like a mason jar, and store in the fridge for up to 1 month. Freeze: Allow to cool completely, and put in a freezer friendly container for up to one year. Reheat: When ready to use, thaw in the fridge overnight, then put the roux back in the cast iron pan, reheat over medium-low heat, and proceed with making gumbo.