Cake in a Jar

I used a package of Betty Crocker Chocolate Chunk Brownies because they are totally delish and just as good as home made.
I filled the jars 2/3 of the way full, baked them at 350 degrees for about 45 mins after having put them on a baking sheet.
Prior to that I sterilised the jars as per the instructions on the box.
When you place the lids on (very gingerly since the jars are very very hot) and tighten them up, the lids pop down during the cooling process so you know they are sealed.  

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