Press liquid from tofu (layer between two paper towels and set something heavy on it) and let drain about 30 minutes. Cut into cubes. Toss with cornstarch and season with salt and pepper.
Stir together prepared PBFit, tomato paste, vegetable broth, ginger and Aleppo pepper.
Place sweet potatoes and turnips into a microwave-safe pan or bowl. Cover with wet paper towel and microwave on high until sweet potatoes are tender, ~3 minutes. (Turnips should still have a bit of crunch.) Season lightly with salt and pepper.
Heat a Dutch oven over medium-high heat and spray pan with cooking oil. When oil is hot, saute tofu until golden brown, ~5 minutes total.
Set tofu aside and keep warm. Return the pan to the burner and reduce heat to medium. Spray pan with cooking spray
Saute bell peppers and garlic about 1 minute. Add sweet potatoes, turnips and peanut sauce and bring to a simmer. Sauce will start to thicken in about 2 to 3 minutes. Add tofu and stir to coat. Simmer for 4 to 5 minutes more so tofu can absorb flavors. Season with salt and pepper. Top with lime juice, cilantro and chopped peanuts.
Stir couscous into stew. Divide into four bowls and serve.