I'm pretty much in the same boat haha.
Always been kinda skinny but I'm pretty lean now too. Workout every single weekday morning, light exercises on weekends which are pretty much my rest days.
Personally I choose to stay away from protein powders. Used to buy them a lot but I feel like there's too much sugar in the stuff. And the good quality ones are too pricey. I feel better without them tbh.
For my post-workout breakfasts I usually just do eggs (scrambled or omelette with veg. Hate eggs but decided to start eating it again to up my protein a bit), high protein yogurt like Greek yogurt or those protein-specific yogurts mixed with almonds and honey, and something like oats or even weetbix with milk, fruit. That's on Mon, Wed and Fri.
On Tue and Thu I might have whole wheat bread/toast or rice cakes with a generous amount of unsweetened peanut butter and topped with tuna mayo (tastes great imo), sometimes avo, and some high protein yogurt again mixed with honey, seeds.
For lunch I might do chicken/veg or chicken salad or something when I can or some sort of healthy sandwich, crackers or whatever, fruit, nuts etc. Whatever I have on the day or can get really. And as South Africans, nothing wrong with some lean biltong to snack on
Things like rice, pasta, potato, red meats, other fish or chicken, other cooked veggies or salads etc I only eat for dinner.
I don't like to eat too much during the day so there's little to no snacking in between.
And I pretty much only drink water and lots of it.