Put the milk in a small saucepan with the oatmeal and turn on medium to medium high heat.
When the milk starts to a boil add the slight pinch of salt and lower the heat enough to bring the mixture to a simmer (usually medium to medium low).
Stir the mixture as it simmers and thickens.
After about 5 minutes on the heat, add the peanut butter, blueberries, and cinnamon.
Stir and cook for another 1-3 minutes depending how thick you like your oatmeal and how cooked you want your fruit.
You will need to adjust your heat to maintain a simmer. I cook mine about 8 minutes total, leaving a little liquid because the mixture will continue to thicken as it cools. The longer you cook the berries, the more of their sugar you will release, and the more of a "jam" they will be like as their pectin breaks down.
Once cooked, remove from heat. Eat and enjoy!