Grill the portobello mushroom, using olive oil if desired. Spread the hummus across the insides of both slices of bread. Add the mushroom and a few pieces of spinach. Place the sandwich in a panini grill for 1 to 3 minutes, depending on desired crispness. Remove and enjoy.
This recipe was created by a contestant during a cooking competition. The Food Network Kitchens have not tested it for home use, therefore, we cannot make any representation as to the results.