You can also use a jarred roasted red pepper if desired.
GLUTEN-FREE: Simply use gluten-free pasta and gluten-free breadcrumbs, or even omit the breadcrumbs altogether. I recommend a pasta that can hold up well to a long cooking time, like brown rice pasta, which I tested this recipe with. It was great!
SOY-FREE: There are several delicious soy-free miso options on the market these days. I keep chickpea miso stocked in my fridge, but I've seen other choices at my local Whole Foods. Is this isn't an option for you, then omit the miso and increase the nutritional yeast a little bit - it's really fantastic with miso, though, and fermented soy is easy to digest!
OIL-FREE: Skip the olive oil in the sauce, for greasing the garlic and the pan, and tossing with the pasta. I tested this recipe both ways, and the texture is better if you use olive oil, but it doesn't make a huge difference.
MAKE AHEAD: The vegan mac and cheese sauce is best when blended fresh using potatoes that are still warm, but you can make it ahead if needed. Heat it back up on the stovetop with a splash of vegetable broth to loosen it back up. Either way the red pepper and garlic can be roasted in advance.
LEFTOVERS: This is best eaten fresh - the pasta tends to start to absorb the sauce as leftovers sit. However, we still enjoyed the leftovers from the refrigerator happily. I recommend adding a little water or vegetable broth and a dash of olive oil to liven them up again. I don't recommend freezing this dish.
NUTRITION: Nutrition facts include the breadcrumb topping and exclude the optional oil.