Place the tortilla on your work surface, then using a sharp knife, cut a slit from the center outward to one edge.
Place each of your fillings in the four quadrants of the tortilla. Starting on the bottom right corn, fold one quadrant up, then across then down to form a triangular pocket.
Add the butter to a skillet set over medium-low heat. Once it has melted, add the filled tortilla and cook until golden brown and crispy, about 2 minutes. Flip it once and continue cooking an additional 1 to 2 minutes, then serve. (Alternately, cook it on a panini press.)