Put the fruit in a small saucepan, mash a bit with a fork or potato masher, and simmer over medium-low heat for 10 minutes. That's it!
Refrigerate for later use. It will firm up if left overnight in the fridge.
If the fruit is particularly juicy and the compote is too runny, you can stir in 1 tsp of chia seeds to absorb some of the liquid.
If the fruit is having a hard time getting started and sticking to the pot, add 1 Tbsp of water to help it along until it starts to release the fruit juice.
Frozen fruit works great for this too.
I like to make a big batch of compote at a time, but because there are no sugar or preservatives added, it should not be canned using traditional methods. It does freeze well though! If I have a lot of fruit to process, I usually make more compote than I can eat and freeze it in small jars with about 1/2 inch of room left at the top to allow for expansion.