I found this recipe at about.com. I used less garlic than the recipes calls for just because I am not a huge garlic fan. I also added some salt and pepper. I cooked this on an indoor grill pan but you could use your outdoor grill.
To make the pea pesto: I put a bag of defrosted peas in the food processor. I added a handful of pine nuts, a big pinch of salt and pepper, and a little chopped garlic. I processed the peas into a puree, and while the machine was running, I drizzled in olive oil until the texture became a thick paste. You could use this pesto with pasta or rice.
1/2 cup tequila
1/4 cup margarine, softened
3 tablespoons olive oil
1/4 cup lime juice
5 cloves garlic, minced
4 portobellos, stems removed
Whisk together the tequila, margarine, olive oil, lime juice and garlic. Allow to sit for at least 10 minutes.
Baste the mushrooms with the tequila mixture, then place on grill.
Allow to cook for 3-5 minutes, then turn and baste with more of the tequila mixture and cook for another minute or two. Top with additional tequila mixture if desired before serving.