Make the filling: add olive oil and garlic to a pan. Saute for 30 seconds. Add the mushrooms and spinach and saute for an additional 2 minutes. Remove the mix from the pan, put it on a plate, and set aside.
On the pan where you cooked the filling, add the butter. Once melted, add the flour tortilla on top. Place the filling on half of your tortilla. Sprinkle cheese on top of the filling. Fold the other half of the tortilla over. Cook until the tortilla is golden and the cheese has melted.
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