My mom used to make these (actually, she still does), and I absolutely love them. They're great plain, or in a salad, or for whatever else you want to use them for! Pickled beets are so simple to make - please, don't buy them pre-made! However, you can start with canned beets in whatever shape you like (whole, sliced, cubed, chunked, etc). If they're big chunks or slices, I prefer them cold; if however, they're cubed, I like them hot.
This recipe easily doubles...triples...multiplies however many times you want to make it.
2 cans beets, drained - reserve the juice (I used whole beets & cut them into chunks)
1 cup sugar
1 cup white vinegar
1 cup beet juice (from canned beets)
Combine sugar, vinegar, and beet juice and bring to a boil over medium heat. After it reaches a full boil, remove from the heat, cool slightly, and pour over the beets. You'll probably have some juice left over, but not enough for a third can of beets. (This works best if you put them into a canning jar & use a wide-mouth funnel.) Two cans of beets (not sliced) will fill up a quart jar. Either keep them in the fridge, or process them according to home-canning directions.