Take the pan off the heat and, aiming for the space around the chicken, grate in the lemon zest, add the garlic and dried tarragon (or thyme) and give a quick stir into the oil as best you can.
Put the silken tofu and soy sauce in a tall jug and add 3 tablespoons of the reserved pasta water. Use a stick blender to blend to a smooth sauce, then pour into the pan with the mushroom mixture.
Mmm! Mario isn't afraid to dig in when he speaks to best friends Danny Biller and Adam Corpus about their new business Daisy's Chicken and Ice Cream in Narragansett. Look for "Mmm! A Food Podcast ...