Preheat oven to 375 degrees. Spray a baking sheet lightly with cooking spray.

Wipe the mushrooms clean with a damp towel. Remove the stems, slice off the bottoms, and mince the stems.

Heat the olive oil in a skillet over medium-high heat. Add the minced mushroom stems, salt, and pepper and cook, stirring, until any liquid the mushroom give off has evaporated and the mushrooms start to brown. Put the cooked mushrooms in a food processor with the artichoke hearts, onion, Vegenaise, waffle crumbs and nutritional yeast, and process until almost smooth.

Using a small spoon, fill the mushroom caps and mound the filling on top. Place the stuffed mushroom caps on the prepared baking sheet, spray the tops lightly with some more cooking spray and bake for 30 - 35 minutes or until the filling is browned and set. Remove to a serving plate and serve.