Mix sugar and salt in a small bowl. In another bowl, combine soy sauce, cooking wine, and sesame oil.
Heat plant oil in a wok or large skillet over medium-high heat. Add diced tofu and sear for 1 minute without stirring, then stir-fry for 2-3 minutes until golden brown.
Add minced garlic and ginger to the wok; stir for 15 seconds until fragrant.
Add julienned beets and cook for 1 minute, stirring constantly.
Add chopped shallot and stir for 30 seconds.
Add chopped beet greens and the sugar-salt mixture; cook for 1-2 minutes until greens wilt.
Add sesame seeds, soy sauce mixture, and cilantro (if using); cook for 1 minute.
Stir in the cornstarch slurry and cook until the sauce becomes glossy and thickened.
Finish with optional crushed red chili and a squeeze of lemon before serving.