If you cut your carrots thin enough, you don't have to cook them to make great quick pickles; just pour hot pickling liquid directly over the carrots and let sit. For more visual punch, use multi-colored carrots.
Ingredients
1 pound carrots, peeled and sliced on the diagonal into 1/8-inch-thick coins
1 cup apple cider vinegar
1/4 cup sugar
2 tablespoons kosher salt
1 tablespoon black peppercorns
1 tablespoon mustard seeds
Directions
Place carrots in a heatproof resealable container or jar. Combine vinegar, sugar, salt, peppercorns, mustard seeds, and 1/2 cup water in a small pot. Bring to a boil over high heat, stirring occasionally. Immediately pour over carrots. Let cool to room temperature, then cover and refrigerate at least 2 hours before serving.