We thought it was very good! We also added bacon. :)
This is a huge hit with all my boys (college kids and husband). Love it for football games. I leave out the onion. I agree that additional cooking time is needed to thoroughly heat and melt the cheeses.
A good sandwich, though I suspect it'd be a lot better with an adjustment on the heating. I made the sandwich with refrigerated meat and cheese and after cooking it for the listed 10 minutes, the meat was still cool and the cheese unmelted. As such, I don't think it was as good as it could be. I believe it'd be a 4 star sandwich with this issue fixed. I recommend either letting the meat and cheese warm up to room temperature before baking or increasing the cooking time and checking to ensure the cheese is melted.
These are quick and easy crowd pleasers. Many grocery stores have flavored focaccia; my favorite is sun-dried tomato. Serve with pasta salad and fresh fruit. Left-overs reheat beautifully.
My family loved this sandwich and I will make it again. I stuck to the recipe. I think it's good to fix anytime. And for people like me that does not know where to locate the pesto, check with the spaghetti sauces.