In a large bowl, add 6 cups of instant oats, powdered milk, brown sugar, salt, and cinnamon.
Put 4 cups of oats in a blender and blend until they're powdery, stopping a few times to shake (if needed). Transfer the oats from the blender to a large bowl and mix with the oats and other ingredients.
Measure ½ cup of the oatmeal mixture and place it inside a zip bag. Repeat the process with the remaining mixture to fill all 20 bags.
Storage:
Store the pre-measured oatmeal packets in the pantry for up to 2 months.
To make oatmeal:
Empty an instant oatmeal packet into a bowl and add 1 cup of hot water. Stir to combine and microwave on high for 30 seconds to 1 minute.
Notes
You can omit the powdered milk from the oatmeal packet mix and use any milk instead of water to make your bowl of oatmeal. Variety of Flavors:
Original: omit the cinnamon and brown sugar.
Apples & cinnamon: add 1 cup chopped dried apples to the bowl.
Chocolate: add ½ cup unsweetened cocoa powder to the bowl, use white sugar.
Cookies & cream: crumble 4 Oreo cookies into the bowl, omit the cinnamon, and use white sugar.
Banana nut: add ½ cup finely chopped walnuts to the bowl and top with ½ banana after cooking the oats.
Cranberry almond: add ½ dried cranberries to the bowl and ¼ cup finely chopped almonds.
Other add-ins:
Chia seeds: ½ teaspoon per packet.
Flax meal: 1 teaspoon per packet.
Hemp seeds: 1 teaspoon per packet.
Protein powder: 2 tablespoons per packet, add additional water if adding more.