Cut chicken, zucchini, and squash into bite sized pieces. (Wash all produce.)
Mix these and mushroom pieces, then sprinkle with 8 teaspoons Cajun seasoning mix (for a milder flavor, reduce to 4 tablespoons – If you are spice-intolerant, like me, 8 tablespoons can kick your butt). Mix well.
Get four large sheets of tin foil (I use about 20 inches) and lay flat. Put 2 tablespoons butter in the bottom of the foil, then add 1/4 of the chicken veggie mix on top of the butter, in the middle, and fold long ends over each other (should almost completely overlap), then fold up short ends. (Don’t fold too tight, you want a little room for the steam.)
Repeat procedure three times. Cook over high heat (450° F on my grill) for about 15-20 minutes. Chicken should be very tender and white all the way through.