Yuzu is getting chubby and I am the problem

Okay so I need to admit something. Yuzu is still a baby on paper but his belly is already round enough that I almost thought he was a different dog when I walked into the living room this morning. The vet in Sattahip (I won't name them, but they are very nice) weighed him and said he is about 300 grams over where he should be for his age and breed. I laughed. Then she did not laugh. I live in a condo on the fifth floor and we do the walk three times a day, so I thought we were fine. Turns out the walk is not the problem. The problem is me giving him little bits of everything. Chicken from the market, a bit of my kaeng liang, cheese on Friday because it is a tradition. My Thai neighbour says this is how every grandma in the soi raises dogs, and yes, I see the logic. Nobody in the soi has a fat dog though. So here is the plan. Treats only for training, cut into tiny pieces smaller than a fingernail. His kibble goes in the bowl at the same time every day, not whenever he looks sad. I also stopped giving him food on the floor because he eats too fast and I think he feels nothing when he finishes. I put a snuffle mat by the sofa and now he spends fifteen minutes on it, which is good for his brain and makes me feel less guilty. Weight check again in one month. The vet said not to worry too much at this age, puppies are supposed to look round. But she also said habits start now. Yesterday he gave me the saddest face I have ever seen and I gave him one piece of cucumber. That counts as a win, right? If anyone here has a chubby pom and found a way to make the diet bearable, please tell me. Yuzu is not impressed with cucumber.