I'm interested in the question, but not proficient enough to translate, so I am posting an incomplete answer (as Stack Exchange discourages discussion in comments).
Given the apparently expressive nature of the English sentence, a fully literal translation seems inadvisable to me. It's obvious of course that we don't want to translate "boy" as "puer", but even other words, such as "got" and "scald", are a bit tricky to translate without understanding what the overall point of the sentence is.
It looks like "Boy, you got a good scald on that chicken!" is an appreciative comment Ed makes after he starts eating fried chicken that his wife made. It does not seem to be a sarcastic insult, but in the context of the movie, the comment seems to come across as dismissive after his wife proposes taking a trip to Florida for the sake of their marriage.
As I understand, the gist of it is "this fried chicken was well fried (by you)".
I think the basic meaning would be conveyed by something like "hic pullus (gallinaceus) frīctus/frīxus bene coctus est!" or "hic pullus (gallinaceus) bene frīctus/frīxus est!". I am not sure whether this has the right expressivity for the context.
How to say "chicken meat" in Latin?
With living chickens, gallus is the male (cock, rooster) and gallina the female (hen), while pullus is the young. The adjective for "chicken" is gallinaceus.
I'm pretty sure that gallus or gallina would be appropriate to refer to meat/a carcass in a situation where you are talking about cooking a mature cock/rooster or hen, but that is not such a common situation in modern cuisine as it probably was in ancient times. From what I can gather, chicken meat bought at the store today generally comes from broiler chickens that are slaughtered before reaching maturity and can be male or female.
So I'm inclined to go with pullus to refer to chicken meat in a modern context. If this word by itself is considered too ambiguous due to its broad meaning (aside from "young chicken", it also means "foal" "darling", etc.), it could be extended to "pullus gallinaceus", as in Celsus below—although that might seem a bit awkwardly long as a translation of "chicken".
I'm not sure whether any of pullus, gallus, or gallina is attested as a general term to refer to chicken meat in Latin (without specifying the age or gender of the fowl).
One attested combination is gallus gallinaceus "poultry-cock". Examples:
Petronius, Satyrica 49.2.2, 49.3.1
mirari nos celeritatem coepimus et iurare, ne gallum quidem gallinaceum tam cito percoqui potuisse, tanto quidem magis, quod
longe maior nobis porcus videbatur esse quam paulo ante apparuerat.
We began to express astonishment at such speed, and took our oath that not even a fowl could have been properly cooked in the time, especially as the pig seemed to us to be much bigger than the boar had been a little while earlier.
(Petronius, Satyricon, Michael Heseltine, Ed—Perseus)
Gallina is used in a culinary context, but as mentioned above, I suspect that in this context it has its literal meaning of "hen", rather than necessarily having the broader meaning of "poultry meat in general". However, perhaps it could have that meaning. I believe hen flesh was the most common kind of chicken meat eaten in Ancient Rome, as unlike in modern times, the same breeds of chicken were raised for both eggs and meat, with males either being culled or castrated (which resulted in capons) (Smith's Dictionary of Greek and Roman Antiquities (1890), agricultura).
I found an interesting article "Pullus, gallus et gallina : déclinaisons antiques" (Nicole Blanc) (in French) which has a section "Alimentation et cuisine" which mentions that the use of hens for food is discussed in Columella's De Re Rustica.
Pullus is used in a culinary context in the late Latin cookbook De Re Coquinaria:
isicia minuta facies quadrata, et coques simul turdos vel aucellas vel de pullo conciso et cerebella prope cocta cum iuscello coques.
et impensam cum condieris, alternis in pullo componis, omento tegis et in operculo deponis et in furnum mittis, ut coquantur paulatim, et inferes.
Due to the lateness of this document, its usage is not too relevant to Classical Latin (we know anyway from Romance words like Spanish pollo, French poulet that pullus or a derivative of it eventually came to be used in reference to chickens and chicken meat).
But pullus (in the context "pullus gallinaceus") also seems to be used in Celsus, in a medical context describing something that is consumed:
De Medicina 220.127.116.11:
iure uel * * pulli gallinacei uentrem resoluere
Where "ius pulli gallinacei" = chicken broth.
As De Medicina dates to the first century, it seems stronger evidence of pullus being used classically in reference to chicken meat. But I am not sure whether there are other examples.
How to say "fried" in Latin?
I think the root that you selected, frīgō, is the best Latin verb for "fry" (and is in fact the source of the English word). Another near synonym is coquo which can mean "cook" more generally. Something well cooked could be described as "bene coctus".
I don't think it is necessary or advisable to coin a new noun frigimentum. A lot of Latinists are reluctant to coin new words; furthermore, although -mentum appears in a fair number of words, I would not consider it an extremely productive suffix like -tio or -tor.