While some people feel a nostalgia when they think of picking currants as children, or their grandmother's jelly, for a lot of us, currants offer a completely new set of flavors. Accordingly, it can be a challenge to learn to use them. If you like tart fruit, they are great for snacking on. But here's a few additional ideas:
Red, white, and pink currants are all very similar, and can be used interchangeably. The red are the most tart, but also have the strongest flavor. White and pink are more mild, and slightly sweeter. Black currants have a very different flavor profile. They aren’t as tart as red, but have a musky or earthy flavor.
For an easy, no-cooking-involved currant topping, pull red currants off the sprigs and mix them with a little sugar (or other sweetener) to taste. This mixture will store in the refrigerator for a couple of weeks. It’s great to put on yogurt, oatmeal, or ice cream. Mix colors together for an attractive fruit salad. I’ve served this with whipped cream at a brunch party.
Black currants are great as used above, but also work well in savory applications. Make a lightly sweetened and spiced sauce to put on meat, or serve with a cheese plate. Put whole black currants in a green salad, especially nice with a goat cheese.
If you like to preserve, red currants make a beautiful and flavorful jelly. I like to add a little cinnamon to it. I usually make jelly using low-sugar recipes with Pomona’s Universal Pectin: http://www.cooksinfo.com/red-currant-jelly. And if you prefer to bake, this looks like a fantastic cake: http://bibliocook.com/2010/08/redcurrant-almo/
Black currants can be a good jelly, but make an even better jam. Here’s a simple recipe, complete with a lovely tribute to one of our most distinctive fruits: http://www.davidlebovitz.com/2013/08/black-currant-jam-recipe/.
For a more ambitious baker, black currants offer deep flavor that can make for spectacular creations. Here's a pair of recipes from Nigel Slater that showcase their special qualities. https://www.theguardian.com/lifeandstyle/2015/aug/16/nigel-slater-blackcurrant-recipes
Black currant juice is also a great thing to pull out in the middle of winter, and simple to make. Just put clean black currants in a saucepan and cover with water. Simmer for about 30 minutes. Mash the currants if you like (this will make the juice less clear, but won’t hurt the flavor), then strain. Sweeten to taste if you like, but cooking takes some of the edge off the flavor, and, depending on your tastes, the juice can be nice unsweetened. This can be canned like jam, or frozen. The juice will be concentrated; we like to mix it with equal parts sparkling water for a natural soda.