First of all, it is important to notice that in order to gain weight you need to increase the overall calorie intake, this is throughout the day.
While it is true that protein and carbohydrate absorption is maximized shortly after exercise (van Loon LJ, 2013; Pasiakos et al., 2014; Naclerio et al., 2017); nutrient distribution during the day is also important, such as having casein before sleep (Kerksick et al., 2017).
In your case, I would, perhaps, look to consume small amount of carbohydrates during the workout (Cermak et al., 2013).
Currently, you are getting 1scoop of whey protein (WP) is about 25g (21g of protein). 3 scoops of Huel contain about 36g of protein. Therefore in your breakfast you are getting about 57g of protein. That is perhaps more than what the body will be able to absorbe easily.
You are getting about 46g of carbs. If you are looking to gain muscle I would recommend you increasing the intake of carbohydrates after your workout. It will help you with recovery and help with the muscle building as protein won’t be used as energy souce. Adding some oats, honey, banana, berries or even some peanut butter for the extra calories if you fancy.
As far as the rest of the days go, you should try to be hitting your macros and being on a caloric surplus of 200+. Make sure you have around 30-40g of protein per meal (reach 1.5g of protein per kg of bodyweight or more); and more than that in carbs.
You can use some tool like bodybuildings calorie calculator to have a rough idea, or MFP.
Without more details is hard to say more. Summing up:
- I would not add an extra scoop but raw carbohydrates in the morning meal (and perhaps some small amount during the workout).
- You can use Huel throughout the day to reach 30-40g of protein per meal. Distribute your protein intake during the day.
- Increase the caloric output for mass gain. Don’t forget about carbs and fats.