Add some cocoa powder (or even better, at least 70% dark chocolate) to a pot of chili for an incredible depth of flavour.
Use half mayo and half sour cream when making dressing for summer salads. Or, depending on the salad, half mayo and half Greek yogurt. Also, if you’re making pasta salad, toss the pasta with oil, lemon juice, seasonings…whatever you were going to use for your dressing *except* the mayo/sour cream and leave it overnight to soak into the pasta. Then add the rest of your vegetables or whatever and the mayo/sour cream. It’ll prevent the mayo from soaking into the pasta and disappearing, but it also makes the pasta itself taste amazing.