These look beautiful cooked whole. But you can also slice them up and add them to rice or potatoes. In the summer, they taste great cooked on a grill. The recipe is adapted from The Italian Country Table by Lynne Rossetto Kasper (Scribner, 1999).
2 large cloves garlic
1/2 teaspoon dried oregano
Generous 1/2 teaspoon crushed dried hot chilies or hot pepper flakes
1/2 cup olive oil
1 pound portobello mushrooms
Purée first 4 ingredients together. Allow to sit for an hour. Remove the mushroom stems and clean the caps. (Reserve the stems for another use.)
Brush both sides of each mushroom cap with the purée and let sit for at least 15 minutes. In a medium sauté pan, grill over medium-high heat until browned on both sides. Reduce the heat and cook 4 minutes longer until tender. Season with salt and pepper.