In a large pan, melt the coconut oil over medium heat. Once hot, place the red onions in the pan and saute for 3 minutes.
Next, add the carrots and zucchini to the onions, stir together the ingredients and saute for 3-5 minutes over low-medium heat, or until the zucchini starts to soften.
Add the corn, mushrooms and tomatoes to the pan, mixing them in thoroughly and cooking together until the mushrooms reduce in size.
Season the vegetable mixture with the basil, salt and pepper.
Take the clean chard leaves and chop off the stem, and if the center rib is thick, skim some of the top off to make it more flexible. If you are using large chard leaves, slice them the center and cut the rib out.
Place the sautéed veggie mixture, in a small line, a little off-center on the chard pieces and roll up. Use a toothpick to keep them from unraveling if need be.
Serve while the fillings are still warm.