For starters, I would try and get a decent estimate as to how many calories you were actually consuming during your period of OMAD. This is because our bodies become accustomed to a certain number of calories when consumed consistently over a period of time. Our metabolism changes based on how much food is available at the time, so if there is less food, you use it more efficiently.
If you introduce a normal amount of food after eating less for a period of time, your body is still working in high efficiency mode which means you run the risk a putting on fat a lot quicker than you normally would. This is why people typically gain a lot of weight back once they’re off a low-calorie diet.
I’d recommend calculating how many calories you were consuming in one meal, and turn that into multiple meals. It doesn’t have to be an exact amount, just not drastically more than you were eating on average.