Unfortunately, canned foods vary in calories and fat content. It sounds like you’re feeding a relatively low fat homemade diet. Look for a canned food that is low or low/med in fat content and less than 400 calories per 12-13 oz can. There are canned foods that are high in fat with around 600 calories per can. You might look over the Low Fat Foods list on the review side. There are canned foods listed there along with kibbles.
Figure out how many calories you’re feeding and try to start feeding her the same amount of calories in canned food.