The recipe you’re about to read was a result of me having a very naughty cheat meal at the infamous Shake Shack a couple of months ago. When my husband & I munched into their ‘shroom Burger, we were immediately transported to junk food heaven. The crispy fried portobello mushroom stuffed with melted cheese topped with lettuce, tomato and shacksauce in between soft white buns was so bad for the waistline but so good for the taste buds.
So inspired by that very sinful lunch, I made it a mission to create A Skinny Dish version of this burger that’s still as juicy & delicious minus all the grease, fat and useless calories. Since I’ve started making them, aside from the fact that I don’t have to wait for a cheat meal to enjoy a juicy burger, I haven’t even craved it because I actually, without being biased, genuinely prefer mine. It does require more time than my other recipes (although still very simple), but I promise that every bite is worth it.
Just a note. Go for whole grain buns such as Granary rolls (or gluten-free if you’re intolerant) so you benefit from complex carbohydrates. If you prefer to go low-carb, use only the bottom part of the bun and make it an open burger. Also, because there’s bread, I prefer to have it for lunch over dinner to avoid overloading my body with carbs at night.
Place mushrooms in a big bowl. Mix all the remaining marinade ingredients in a small bowl and pour evenly over the mushrooms. Make sure they are well coated at the bottom as well as top and leave to marinade for 45 mins - 1 hr.
Mean while, prepare caramelized onions using the ingredients above and follow the instructions here. This will take you about 45 minutes so by the time this is done, the mushrooms will be ready for cooking.
Heat the griller to medium/high. Scrape off the garlic & rosemary bits from both sides of the mushrooms (to prevent it from being too pungent), punch small holes with a fork and place on the grill - gills facing up first. Grill each side for about 4-5 minutes, depending on the thickness of the mushrooms, until both sides are well cooked through. Throughout the grilling process, constantly pour strained marinade liquid on the mushrooms to give extra flavor.
Spread 1tsp of mustard on bottom half of each bun.
Top each burger with a handful of lettuce followed by 4 slices of avocado.
Divide the caramelized onions equally and placing half portion over the avocado on one bun and half on the other followed by 1 tbsp of Ricotta cheese on each.
Place 1 mushroom, gill facing down, over the cheese on each burger before topping it all with the top part of the bun.