"Thank you." Senku is polite enough barely to know that's the correct response to praise, and he is proud of it - even though it's just ice cream, and he's made far more impressive things. However, this was made specifically to please other people.

"I was one of the stranger requests I had gotten, but I think it turned out well. The other was the onion and garlic request. I took a similar tactic with that one in the end."