Add 6 cups of Planters Dry Roasted peanuts into a food processor. Process on high for 1 minute. It will still be semi-chunky. Similar to the middle picture of the peanut butter process showed above.
Remove 1/2 cup of the peanut mixture and set aside for the peanut butter crumb topping.
Continue to process on high for 5-6 minutes until the peanut butter is smooth. There may still be a few small chunks. They won't hurt anything.
Place in a bowl with a lid and refrigerate for 2 and half hours until the peanut butter is slightly firm. This will help the piping for the fluffernutter spread.
Peanut Butter Crumb Topping
In a large bowl, add in the butter, brown sugar, peanut butter, flour and the 1/2 cup of reserved peanut crumb topping. Use the peanut butter you just made.
Using two forks or a pastry cutter, cut until it becomes moist crumbs. Place in the freezer for at least 5-6 hours. I left mine over night. This will keep the crumbs in their crumb shape on top of the muffins.
Preheat oven to 400 degrees. Line a cupcake sheet with baking liners.
In a large bowl, add in vegetable oil, brown sugar, eggs, vanilla, milk, peanut butter, baking powder, salt, and flour. Mix with a spatula until thoroughly incorporated.
Fill the cups 3/4th full of muffin batter.
Add a layer of peanut butter crumb topping.
Place in the 400 degree oven for 15 minutes. Reduce heat to 350 degrees without opening oven and let it bake another 9 - 11 minutes until done. Place a toothpick in the center of the muffin, if it comes out clean or with a few moist crumbs, they're are done.
Let the muffins cool for about 20 minutes.
Using a 230 tip, place it in a disposable piping bag. Fill the bag with marshmallows and microwave for 25 seconds. You can also use an apple corer instead of a 230 tip. Place 1 and 3/4th cups of marshmallows in a medium bowl. Heat in a microwave for 30 seconds. Place in a sandwich bag or disposable piping bag and fill the whole you made with the corer.
Place the marshmallows in a large bowl. Microwave for 30 seconds. Stir. If it still have lumps, microwave another 30 seconds. Place in a sandwich bag or disposable piping bag.
Add the chilled peanut butter in another piping bag or sandwich bag.
Start filling pint jars with the peanut butter. Fill about 1/2 an inch and then do the same with the marshmallow. Keep alternating until the pint jars are full. You should get 2-3 pint jars full.
Decorate jars to your taste. I used burlap and some tags I bought at Walmart.