In a large pan or wok, saute the red onions, garlic, mushrooms, and bell peppers until the onions are translucent.
Make a well or hole in the pan using a spoon to move the vegetables aside, creating a hole in the middle of the pan.
Then, add the yellow curry paste to the center of the pan and stir until it begins to break down.
Add ½ cup coconut milk and continue stirring.
Next, add the 2 cups of vegetable broth, soy sauce, and maple syrup.
Bring to a boil and add the broccoli and cauliflower; stir into the mixture, and cover.
Reduce to simmer, and allow to cook for 10 minutes.
Remove the cover and add another ½ cup of low-fat coconut milk and ½ cup of chopped Thai basil.
Add salt and pepper to taste.
Serve with rice or noodles or on its own.
Add roasted cashews and more Thai basil if desired.