food: how little? how often?

I eat the same lunch Mon - Fri at work. Jakcet Potato, tin of tuna (in olive oil) 112g drained weight 30g protein and some salad thrown in. My bf% fluctuates around 10-11% and I'm striving for that single digit % for the first time. The rest of my diet I think I have sorted but this lunch time meal is making me quite full. So my question is, would it be beneficial to cut this meal in half and put a 1 to 2 hour gap in between? Or would I be starving myself of the necessary amount of nutrition that I need for a single meal. I train 4-5 times a week so nutrition is key but just thinking of ways to nail that last 1 to 2 %bf. Any advice would be greatly appreciated.

Cutting meals into smaller ones is a good idea, especially if you're getting too full. There is no minimum size needed for any meal, as long as you are getting enough total nutrition.