As per Vegan.com, there is at least one book that deals with preparing homemade vegan cat food, although I am pretty sure it does not discuss lab meat. Nonetheless, it may touch aspects such as nutrients, storage, and introducing the new food to the cat (aspects which are covered scarcely over the internet).
Also, to answer the question more specifically, there is no 'best way' to do this. Each cat is unique and will respond differently to different recipes or styles. It takes an entire book to cover these aspects.
Nonetheless, given the health concerns over vegan cats being exposed to Feline Lower Urinary Tract Disease (FLUTD) - due to larger alkalinity of vegan diets - I would not take it for granted that what I buy at a supermarket and is intended for human consumption would work great for a cat. Even vegan (e.g. plant-based and commercially available) cat food can be nutritionally inadequate (as per the same article I mentioned earlier). You may be a pioneer in this, but do this at your own (and cat's) risk, while monitoring cat's health and urine pH (as also instructed in the link). You may not know how much taurine or arginine is in the lab meat. You may not know which and how many of each vitamin to add in the food to make it healthy for the cat.
Also, lab meat may contain substances or chemicals harmful for the cats. In addition, the lab meat seems to be in its infancy. There are concerns regarding the proper culture medium and the nutritional value of the lab meat. Nutritional deficiencies of lab meat seem common at the present, and make it unable at the moment to be implemented in pet food. Check out this article for a good discussion on the topic.
To conclude, I think it is a very, very long way for you to make cat food at home using lab meat. It requires a lot of research from your part to provide a 'complete and balanced' food (minerals, vitamins, nutrients etc.). It also requires you to know the nutritional specs of the lab meat, which may vary.