I've been using pumkin/squash, but I've noticed that it has way too much Vitamin A, which can be unhealthy.
I've also tried substituting it for Sauerkraut, but it doesn't go well with all dishes.
Honestly, I wouldn't worry about vitamin A from plant sources. Often, the body can't even convert it to the bioavailable form. It's excess retinol that is being blamed around here. If you get enough of that already, your body will probably not convert the stuff in the squash.
But the rule is in general that more orange = more A. Paler squashes have less, as do parsnips compared to carrots.
Otherwise, why not try mushrooms? Or mashed celeriac.
Also, cauliflower pizza crust: http://www.examiner.com/x-355-Low-Carb-Examiner~y2008m6d4-Cauliflower-Pizza-Crust-Worth-its-Wow-in-Gold
Everyone is coming up with great side dishes, but I think we sometimes have a problem with old mind-sets. Who says we even need to find a substitute for a side of potatoes? If you must have a white component, what about mashed cauliflower?
This is along the line of my own weird mind set of "healthy whole grains". That phrase was rammed into my head for so long that it is hard to overcome.
A healthier frame of mind would be to just accept the concept of a nice piece of meat accompanied by your personal choice healthy side of veggie as the perfect paleo meal.
I like zucchini (courgettes) as a side-dish. If you cook them just right, they can actually have a mashed potato-like texture. Leafy greens like spinach or kale are other favorites, and broccoli or cabbage can also be good. Sometimes I mix in a few sliced onions for variety.
If you're not a big vegetable fan, it's amazing how much better they taste when cooked in lots of butter or cream.
I agree with Melissa. The problem with too much vitamin A is usually via the preformed kind, not from carotenoids in veggies. That said, one of my fave sides is brussels sprouts. Like Rick, I tilt PaNu so do include some dairy, and brussels sprouts in butter are delish!
One other suggestion: I was watching Food Network and saw a great side I want to try: roasted grape tomatoes (just tomatoes, garlic, and olive oil). They'd probably work just as well pan fried.
In my opinion, even better than pureed cauliflower, are pureed turnips, parsnips or rutabega. Or even combining them in some way. Be sure to add butter and/or cream. Yum. These are higher in carbs than cauliflower, but still lower than potatos.
I am a big fan of oven roasted cauliflower for dishes that are traditionally accompanied by potatoes; in my opinion this method gives the closest "mouth feel" to potatoes, and is so delicious that it is completely worth eating in its own right. This recipe is pretty close to what I do, except that I mince the garlic and use half olive oil/half coconut oil. (butter is also awesome here if you eat it)
As variations to garlic, I have also seen it prepared this way with fennel and onions, or Parmesan, or chili and lime, or turmeric jalapeño ginger.
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