Bring a medium saucepan of water to the boil for the pak choy and noodles. Trim the pak choy and separate the leaves. Finely chop the spring onion. Crush or finely chop 2 garlic cloves. Quarter the tofu pieces.
Step 2 — Make sauce
Combine the garlic, peanut butter (see Kitchen notes), Chinese barbecue seasoning, 2 tbs soy sauce, 1 tbs white vinegar and 2 tsp sugar in a bowl.
Step 3 — Cook pak choy and noodles
Cook the pak choy in the pan of boiling water for 1 min or until just tender. Transfer to a bowl with a slotted spoon and return the water to the boil. Add the noodles to the boiling water and cook for 3 mins or until tender. Drain, then rinse under hot water to prevent the noodles from sticking. Return the noodles to the pan, add 2 tsp vegetable oil and toss to combine.
Step 4 — Warm tofu
Meanwhile, heat 2 tsp vegetable oil in a medium frypan over medium heat. Cook the tofu, turning, for 4 mins or until golden and heated through. Add the sauce and half the spring onion and cook, stirring, for 1-2 mins until the sauce is slightly thickened. Remove the pan from the heat.
Step 5 — Serve up
Divide the noodles, pak choy and tofu mixture among bowls. Scatter over the remaining spring onion and enjoy!
Step 6 — Kitchen notes
Peanut butter can firm up upon sitting, so give it a good mix to soften and bring together. ~ Like it hot? Kick up the heat a notch or two by scattering over chopped fresh chilli or chilli flakes before serving.