I have a lactose intolerant cat AND a cat who doesn't tolerate beef well. The lactose intolerant cat does not do well with fish, either. Basically, I feel foods with poultry. Then they're both happy.

The lactose intolerant cat LOVES yogurt. He even tried to drink my chai latte? That is definitely something I would never have expected to appeal to a cat, but there he was, dunking his drinkin' paw in there.

My two were eating EVO and I was transitioning them more to canned until the orange beast developed pancreatitis. I had to cut out the EVO, which is higher in fat, and put them on a low-fat diet. They're eating Innova Low-Fat right now, which they seem to like reasonably well. He doesn't love the canned food, but I offer it anyway and I'm just happy he's eating anything.

For finicky-tummied cats, I've had good luck with California Natural. This same kitty had an AWFUL time as a kitten with different foods, but California Natural, which was among the first foods for cats with allergies, worked really well for him for years. It's just chicken and rice. It definitely settled his digestive tract right down.