Preheat your oven to 425°F (220°C). Wash the beetroot, wrap in foil, drizzle with olive oil and sprinkle salt. Roast for 50-60 minutes until tender.
Soak the cashews in hot water for about 30 minutes. Rinse in cool water after soaking.
Bring a large pot of salted water to boil. Cook the pasta according to package instructions, reserve 1 cup of pasta water before draining.
In a skillet, heat olive oil over medium heat, add shallots and black pepper. Sauté for about 5 minutes, then add garlic and cook for another minute.
Peel the roasted beets and blend with soaked cashews, sautéed shallots, salt, and a splash of water until smooth.
Combine the blended sauce with sautéed shallots and garlic, stir in reserved pasta water, sugar, herbs, and red pepper flakes. Heat gently for 5 minutes.
Toss the cooked pasta in the sauce until evenly coated, adding more pasta water as needed for desired consistency.
Serve garnished with fresh basil, nutritional yeast, or cracked black pepper. Enjoy immediately.