One of the joys of fresh produce for me is being able to make fresh smoothies at home at almost any time. Sure, I could run to Smoothie King during the day, but I can make just as good of a smoothie at home in a couple minutes with less than half the ingredient cost - and even if it's 1:30 in the morning.
Tonight, that happens to be a peach-blackberry smoothie, but the recipe is pretty flexible. I'll note it, and then note substitutions. The key is always having quality fresh produce.
Wash the blackberries and peaches; add the blackberries to your mixing container. Slice peaches and add to container; eat remaining 1/2 peach. Add ice cream, then fill container with milk so that fruit and ice cream are mostly/entirely covered. Mix with immersion blender (if available) or regular blender. Serve.
The core recipe is super flexible. If peaches aren't in season, I often make banana-blackberry. If raspberries are on sale, they make for an excellent choice. I've made it as banana-blueberry before. There are a lot of options. I do recommend orchard peaches if they're available in your locale, as they tend to be much more flavorful and be much closer to the peak level of ripeness than storebought peaches.
I also will sometimes use orange juice instead of milk, making a peach-banana-orange smoothie, for instance. It depends on what I have in the fridge at the time. 2% milk also works well.
The ice cream is optional; the local ice cream mill Velvet came out with a really good peach flavor this year, so I've been adding that. But it turns out well without ice cream too, as long as you have good fruit.
I like to make individual servings with an immersion blender; with a sufficiently large glass you can simply mix it in the serving glass. For larger groups, a traditional blender may be preferable.