Its important to distinguish between low carb like atkins / pig to twig whereby you eat so little carbs that your body goes into ketosis - on these diets you can't "cheat" because any significant level of carbs will bring the body out of ketosis. On these diets you need to get calories from somewhere so they are generally higher fat diets.
As food substances go - meat, hard cheese and eggs have hardly any carbs.
Alternatively you can do a lower carb diet - where you cut down on carbs but don't go for a ketosis diet. This means that you do have some carbs eg those contained in whole fruit, dairy, pulses and perhaps occasional whole grains (eg brown bread, oats, brown rice) but the carb level is much lower than normal eating. I combine this with low fat....
I do cook from scratch but def not any fancy dishes! This is NOT a ketosis diet though.
some examples:
breakfast - 2 egg omelette and activia fat free yoghurt or natural low fat yoghurt, with oatbran, berries and small serving (25g) sugar free muesli.
Around 250 cals.
lunch:
salad with protein - generally cottage cheese, tuna, makeral, sardines
Around 250 cals
dinner:
chopped tomatoes plus lean beef mince (or quorn or chicken mince) and lots of veggies all chucked into wokl
or stir fry with veggies, chicken (or quorn) and brown rice
or steamed fish and veggies.
Around 500 cals
snacks (200-300 cals)
2 pieces of fruit (not banana or exotic fruit - generally apples best)
activia yoghurt
cottage cheese on a ryvita
smoked salmon and quark on an oatbcake
25g nuts or 25g hard cheese