Combine vegetable broth, soy sauce, rice vinegar, maple syrup, cornstarch, sriracha, ginger powder, and minced garlic in a bowl, mixing thoroughly until smooth.
Heat a wok or large frying pan over medium heat and pour in the coconut oil, then add thinly sliced onions, cooking them until just soft, about 2-3 minutes.
Add sliced mushrooms, shredded cabbage, and julienned carrots to the pan and toss continuously over medium-high heat for 5-6 minutes, seasoning with salt and black pepper to taste.
Stir in the drained canned lentils and freshly whisked stir-fry sauce, gently mixing everything together.
Allow the mixture to simmer while stirring occasionally for 2-3 minutes, until the sauce thickens and coats the vegetables.
Plate the stir fry alongside cooked rice and finish with a sprinkle of chopped spring onions for garnish.
