Pre-heat oven to 450F.
Line a baking dish with tin foil. Wash beets and trim the leaves/stems back (leaving an inch or two) if your beet has any. Don't trim the tails as you'll lose juice (and thus flavor) while roasting.
Add beets to the foil-lined baking dish and then cover with tin foil. Roast for at least 45 minutes. Check if beets are done by inserting a skewer. If it slides in easily (through the beet's centre), they're done.
Remove from oven and let cool for 5-10 minutes. Peel beets (I used a knife). Cut beets into 1/4 inch slices and then cut the slices smaller if desired.
While the beets are cooking, prepare the dressing. Chop the basil and mint and mince the garlic. Add basil, mint, garlic, lemon juice, olive oil, and salt and pepper to the Greek yogurt.
You can plate this in two ways. 1) Just before you're ready to serve, cut the bottom of the endive off then carefully take the leaves off. Line the leaves with the yogurt dressing and then arrange pieces of beets as desired. 2) Roughly chop the endive and toss it with beets and the yogurt dressing. Garnish either method with fresh lemon zest if desired. Serve immediately.