People will always recommend reducing your caloric intake, but given that you feel hunger that's not sustainable, even if it were to work for you (it might, but it also might not, weight loss is a very individual thing).
I will suggest to you that your goal should not be to lose weight or for any specific weight target. Your question suggests your issue is that your jeans are too tight for you, so if anything your goal should be too lose inches (which might actually involve gaining weight, as counter-intuitive as it seems).
A strength training program would be advisable. Core muscles that keep your stomach in will make it easier for you to fit into your jeans, although I'm not going to suggest doing ab exercises like crunches. The core muscles are there to stabilise your torso, so doing heavy lifting that forces you to contract your core muscles to keep it rigid will work your muscles the way they are designed to work. These exercises would be squats, deadlifts, presses and chin-ups.
For a beginner to a strength training program, simultaneous fat loss and muscle gain is often possible, so you'll start working towards your real goal of losing inches, even if in that process you start gaining weight (for the same volume, muscle weighs more than fat).
You could modify your diet to avoid feeling hunger as much. Experimenting with the glycemic index or glycemic load diet could work (although for people who have certain conditions, that's actually a bad idea, so pay attention to how you feel after making any changes to your diet). Generally eating foods that are slow to digest (fats, then proteins, not carbs unless they're with fat or protein) could help.
There's also a hypothesis that ex-smokers eat a lot because moving food to their mouths keeps their hands busy. I'm not sure how much truth there is to it, but it wouldn't hurt to find a hobby or habit that generally keeps your hands busy.