Preheat the oven to 400°.
Place beets in a baking dish, drizzle with oil, and sprinkle with salt & pepper.
Cover with foil and roast for an hour until tender.
While beets are roasting, whisk together mustards, honey, vinegar, olive oil, lemon juice, and salt & pepper.
When the beets are done, rub the skins off and slice thinly. Toss with a couple tablespoons of the vinaigrette.
Shape the log of goat cheese into 1/2-inch slices.
Combine ground walnuts and panko in one small bowl and egg yolks and water in another small dish.
Dip cheese slices in egg wash, then coat thoroughly in bread crumbs. Place on a baking sheet and refrigerate 30 minutes.
Heat an inch of oil in a large skillet or wok until very hot. Cook the cheese in batches about 1 minute on each side, until crispy and golden brown.
Divide the rocket among 4 plates. Top each with roasted beets and cheese slices. Drizzle with vinaigrette and sprinkle with walnuts.