Preheat oven to 450°. Divide beets between two sheets of foil, and sprinkle with ½ tablespoon olive oil. Add salt and pepper; then wrap up foil around the beets. Roast beets on baking sheet around one hour and 20 minutes (you should be able to slip a knife in).
In the meantime, whisk balsamic vinegar, poppy seeds, shallot, and two tablespoons of olive oil together in a medium bowl; season with salt and pepper. Set vinaigrette aside.
Once cooked, remove the beets from the foil with a fork, and place them into a strainer. Drain the beet juices from the foil into the vinaigrette, and mix until the vinaigrette turns a reddish color. Run cold water over beets, and rub off skins using a paper towel. Place beets on a tray, cut them in half, and crush them gently with the bottom of a mug.
Heat three tablespoons of sunflower oil in a large pan over medium-high heat. Add beets, season with salt, pepper, rosemary and one tablespoon olive oil and cook until browned (about four minutes per side). Transfer to plate with cheese, and top with vinaigrette.