Hermione was completely lost in thought, watching all the people passing, to even hear his footsteps as he got closer. When he spoke, she jumped a little, being jolted out of her thoughts quickly. She turned to face him, pretending that she hadn't been given a fright by him, a smile on her face.
"You've been here longer than I have," she told him, trying not to giggle nervously.
It was true, she wasn't exactly sure of what was here and she wasn't fussy when it came to food. Neither was Ron, she knew that, but she didn't want to risk mentioning some form of food or a certain restaurant only for him to shoot it down, or go there and be in a mood the whole time. So she would let him decide, and would go along with wherever he wants.