Looking for low carb sauce/seasoning options

Herbs and spices are my go to options - many are simply sprinkled onto the food when put into a closed dish for serving, so non of the aromatics are lost. Be careful doing it though - start off with a small amount - like half a pinch, as some things can be rather powerful.

For cauli rice, try frying some mustard seeds until they pop. Add some lemon skin and fry until it starts to go crispy. Add cauli rice and fry. You could add chili flakes if you like. Another good flavouring is garlic. There are also loads of recipes online for cauli rice dishes. This is just 1 that I found: https://peaceloveandlowcarb.com/chinese-sausage-fried-rice-low-carb/

For noodles, you could use pesto and cream for a sauce with whatever veggies and meat / prawns?

I suggest that you have a look at the dietdoctor.com website.
I have been cooking for decades, and have a low boredom threshold, but the recipes on there taught me new things about herbs and spices, flavoured butters and herb combinations. I’m still using them regularly.
And the best thing about the butters is that you can make up a whole pat of it, chop it into portions and then store in freezer til needed. Then you just drop them onto your hot food and they melt over it.

I use different spices / flavourings, I do a variety of versions of cauliflower rice, a ‘Pilau’ style one where I add chopped onion, garlic, ginger to the butter, maybe a bit of cumin and coriander spice, maybe cardamom pods. I do a ‘chinese’ inspired one with garlic, coconut oil, Chinese 5 spice, chopped onion, maybe add prawns and cashew nuts. My go to cauliflower cheese involves warming together Seriously Strong cheddar spread and double cream, absolutely delicious and just the right consistency. But a go to sauce for me is out of the Old Atkins book, fry finely chopped shallot, add lemon zest, finely chopped, juice of half a Lemmon and a good slug of double cream. This works brilliantly with any fish, chicken, pork, all the ingredients added to the drippings in the pan the protein was cooked in. But just pan drippings alone, if you’ve cooked in butter, maybe with a few fresh herbs, make a gorgeous sauce.