The term "cooks with gas" is typically used to describe someone who is efficient, speedy, and effective in their work. Antonyms for this phrase could include someone who is slow, sluggish, or inefficient. Alternatively, the opposite of "cooks with gas" could be someone who is disorganized, inexperienced, or bumbling. Those who do not cook with gas may also use alternative methods of cooking, such as electric or wood-burning stoves, which can require more time and effort. Regardless of the synonym used, the phrase "cooks with gas" is commonly used to describe someone who excels in their profession, and is highly valued in any workplace.