Either way, although the slow roasting time is, well, slow, the end result is worth it. Marinating the beets in toasted sesame oil and coconut vinegar (always my acid of choice, but you could probably also use white balsamic or even apple cider vinegar) at the end makes these already soft and silky beets even more so.
The marinated beets are then drenched in a homemade teriyaki sauce right before serving, then piled over steamed rice and accented with a little ground nori. I used ochazuke wakame seasoning (which can be found in most Asian supermarkets) instead of nori for leftovers, which also worked nicely with the texture and flavor of the teriyaki beets.
for the teriyaki sauce (yields 1 cup sauce)
1 cup brown sugar
1 cup mirin
1/4 cup sake (if you don't want to use sake, just use 1/4 cup extra of the mirin)
1/2 cup soy sauce
1 TB toasted sesame oil
1 TB minced ginger
1 lb golden beets, (3 small beets)
2 cups coarse salt, plus more if needed
1 TB toasted sesame oil
1 tsp coconut vinegar
1/3 to 1/2 cup cup teriyaki sauce
1 tsp nori dust (grind 1/4 sheet nori in coffee grinder) OR ochazuke wakame seasoning, to taste
2-4 scallions, chopped
1 TB sesame seeds
steamed broccoli or other green vegetable
To make the teriyaki sauce, whisk the brown sugar, mirin, sake and soy sauce in a bowl. Set aside.
Warm the toasted sesame oil in a small saucepan over medium heat. Add in the ginger, making sure it's coated well with the oil. Saute for 1 minute only.
Pour the contents of the bowl into the saucepan, whisking it initially to dissolve the sugar. Once it comes to a small boil, reduce the heat to its lowest setting. Allow to reduce for 30-35 minutes, whisking it occasionally, then remove from the heat.
Chill the teriyaki sauce to allow it to thicken before using. If it become too thick, a few seconds in the microwave will loosen it up enough to pour.
To slow roast the beets, preheat oven to 375.
Pour the salt into a glass pyrex large enough to place the beets on in a single layer. Trim the stems from the tops of the beets, but do not slice off the top of the beets themselves. Trim any tails off the beets, making sure you don't lop off the base of the beets. Rinse the beets and place into the salt while wet. Make sure that the beet has a good layer of salt on the bottom, and the beet itself does not actually touch the bottom of the pyrex. Place into the oven to roast for 2 hours.
For a different, more "meaty" texture around the edges, place one cup of salt in the bottom of a pyrex large enough to place the beets on in a single layer. Place the other cup of salt into a bowl. Rinse one of the unpeeled beets, then place into the bowl of salt. Pack as much as you can around it, then place it onto the bed of salt in the pyrex, ensuring there is enough salt on the bottom so the beet doesn't make contact with the bottom of it. Repeat with the remaining beets. Place into the oven to roast for 2 hours.
Remove from the oven. Allow the beets to cool slightly and remove from the salt. You'll want to peel and mandoline them while they're still slightly warm.
Slice thinly with a mandoline or sharp knife and place into a clean glass pyrex. Whisk the sesame oil and coconut vinegar in a medium-sized bowl. Toss the thinly sliced and still-warm beets into the mixture to coat. Cover and allow to marinate for a few hours or overnight.
To serve, spoon the rice into two bowls. Toss the beets with the desired amount of teriyaki sauce and place over the rice. Sprinkle with the nori dust, and garnish with the scallions and sesame seeds. Serve immediately with steamed broccoli or other green vegetable of your choice.
To make a swirl pattern like this, just lay the sliced beets on a long row so they are overlapping each other. Once you have about 5-6 inches of beet slices laid out, just roll them up to create a swirl pattern.