Mix all the ingredients together in a large bowl. Spoon the mixture into clean mason jars (about 3/4 of the way up). In a separate bowl, mix together the rest of the brown sugar, the flour and oats. Cut the butter in until it is combined. Top the mason jars with the crumble mixture.

At this point you can either bake them at 350 degrees for about a 3-40 minutes (or until hot and bubbly) or you can put the mason jar lids on a store them in your freezer.

If you are baking them from the freezer, take the tops off and place the jars on a baking sheet. Put the baking sheet into a cold oven and turn it onto 375 degrees. This will take about an hour but will ensure the jars won't crack and break.

Serve these hot with a scoop of vanilla ice cream