I was shocked that no one had rated this yet after almost 2 years, so here it goes. I tried this recipe cause it sounded amazing, and it definitely didn't disappoint. The burgers were moist and the mushroom mixture gave them incredible flavor. I followed the measurements for the arugula but added some extra truffle oil cause I really love the flavor. My husband raved about the burgers and says we have to make them again. I served them with oven roasted fingerlings with garlic and parmesan, and grilled asparagus. It was an elegant looking meal considering it is a burger, but definitely a gourmet burger. Will be making it again for sure!