Preheat oven to 375ºF. (See recipe notes for other cooking options)
Place beets in a deep, lidded baking dish (or foil packet placed on a rimmed baking sheet) in a single layer. Drizzle with olive oil and season with salt and pepper.
Cover and bake for 60 to 90 minutes, until tender. Remove from oven and set aside until cool enough to handle.
Peel cool beets (a paper towel makes this very easy) and coarsely dice. Transfer diced beets to a clean, 1-quart canning jar.
Combine vinegar, water and honey in a 2-cup glass pitcher. Whisk until honey has dissolved. Season to taste with salt and pepper.
Pour pickling liquid over beets in jar (you may have a little left over), cover and refrigerate.
Refrigerate for several hours or overnight before eating - the longer they marinate, the stronger the beets will taste.
You can also boil or steam beets for this recipe instead of baking. To boil, place beets in a large saucepan and add water to cover (and 2 tablespoons of vinegar or lemon juice if you want to reduce color bleeding). Bring to boil then reduce heat and simmer, uncovered, 45 to 60 minutes until tender. Drain beets and rinse with cold water (to speed cooling process); let cool to warm room temperature (cool enough to handle). Peel then proceed with recipe. To steam, place in a steamer basket over a couple of inches of boiling water; cover and steam 30 to 40 minutes until tender. Peel once they're cool enough to handle and proceed with recipe.
This recipe also works great for other beet varieties like golden and chioggia (striped).