Sitting back in his seat, Peter let her go to work on collecting the ingredients and, when she wasn't looking, he took his time to watch her collecting them, watching the woman he found so beautiful and gorgeous. He'd always thought her hot, obviously, but when she'd come onto him, it had done quite a bit to make him start thinking beyond just the initial thoughts of her attractiveness. He noticed it more, on a different level.
When she returned he smiled up at her and looked at the cauldron, then back to her and finally his grin tightened and he nodded, "Yes. When you're making a potion, precision matters. It's best to measure out everything how you want it, immediately. Some ingredients have to be dropped in right after chopped, so in those instances, save them for when you need to do it, but have everything else ready to go. That way, all you really have to concentrate is the when to put it in, and where in the order. Rather than 'I have to put this in now, but it's not ready', and you chop or grind far too quickly."
He then whisked his wand at the cauldron, and it cleaned itself, "Do it again."