Coming off of vegetarianism, I found it easiest to start with pulled/stewed meats. Stuff like pork shoulder, beef brisket, chuck steak, rotisserie chickens, etc. where the meat is cooked low and slow (usually in a crockpot, or braised forever in the oven) until it's practically falling apart. The texture is more meat virgin-friendly than a steak or chicken breast, and you're less likely to run into nasty gristly pieces.
“The whole concept of a macronutrient, like that of a calorie, is determining our language game in such a way that the conversation is not making sense." - Dr. Kurt Harris