Such sauces are suitable for a variety of dishes (cheesecakes, casseroles, pancakes, meat, cheeses, etc.) and incredibly decorate them. I mainly make sauces from blueberries, cherries, strawberries, lingonberries and their mixes. More from plums, apples and their mixes. Of course, depending on the particular dish, the recipe will be slightly different, but globally the ingredients and technology are almost the same. Therefore, I will tell you about the principle that you can repeat or take as the basis of your sauce.
So, for sweet dishes, sauces I do this: wash the fruit, if necessary, then take out the bones, peel, etc., put it all in a saucepan and start to heat very slowly so that the berries-fruits give juices. At this stage, you can add a little sweetener (I have agave syrup or Jerusalem artichoke) to speed up the process of separating the juices. I do not add water, as is often recommended in recipes. Well, why, if fruit is water.
Then, over low heat, warm the fruit to a boil and turn it off. Cool for 10-15 minutes and resume the procedure. Usually on the third time of such manipulations, the fruits will be ready, and their juice will turn into a pleasant sauce.
The iterative method helps not to turn the fruit into a dead brew and easily adjust the density of the sauce (you need to look at the consistency at the moments of cooling!).
Seasonings are added almost at the very end of cooking, usually cinnamon, vanilla, a little nutmeg, rum/wine/brandy, more sweetness, if required. First I put a little of everything, then a few times in the process I try and balance the taste.
For cheese, meat and snacks, cooking is simply a set of spices. Instead of alcohol, I put balsamic vinegar/wine vinegar, salt, freshly ground pepper, thyme, rosemary and other spicy herbs according to mood.
Nuances:
In no case do not interfere with the berries, if you need to preserve their structure in the sauce. In this case, only regular shaking of the saucepan is suitable.
Less juicy fruits I cook, covering with a lid so that moisture does not evaporate. If there is a lot of juice on the contrary, then, accordingly, without a lid.
This sauce is perfectly combined with baked camembert or brie cheese.: 
With fried suluguni or Adyghe cheese:
