I am new here and I haven’t even tried Huel yet, still waiting on my first shipment, but it has been my experience from other meal replacement powders that using scoops can be an unreliable way to measure depending on how much the scoop is packed. One scoop can be 20% off either way. The best way to ensure you are eating the correct amount is to measure with a kitchen scale. According to the nutritional values, 500 calories is 127 grams, so for every 100 calories you wish to make your meal add 25.4 grams of powder. I typically had 300 calorie meals so I will add 76.2 grams of powder and see how that works for me in the beginning. Scales are pretty cheap, I have one for home and one for the office, I think they were like 9 bucks on amazon.