Most days if I stick to my meal plan.
Our dietitian at The Priory was very good at encouraging us to try all sorts of foods, she really encouraged us to have chocolate bars or sweets or biscuits as snacks. We had Nutrition groups where she'd bring in lots of different foods (e.g. carbs one week to look at portion sizes, one week she brought in lots of yoghurts and dried fruits, one week chocolate and sweets etc) so we could swap our normal night snacks and try some of those instead.
So now if I stick to meal plan, I might have e.g. one snack as yoghurt and fruit, or something fruit-based to feel a bit healthier, and one snack might be a chocolate bar, 3 biscuits, a mince pie, whatever. It's not a massive proportion of the meal plan, but as a small part of an everyday diet it is fine.