Can I and how do I hit on a restaurant's chef?

So basically I found a chef of restaurant who is a mature japanese guy a very attractive.

He is present often because the restaurant is relatively small.

I met him two days ago and im in his restaurant again, I lost all my confidence i had before. I even learned some honorific pick up line in Japanese but I'm not sure if its appropriate to ask him if he has a partner etc.

I didnt find his social media aside from restaurant I don't

What do I do? Im in his restaurant right now and I ordered a cup of umeshu wine to gain some confidence and dessert.

Is it appropriate to try to pursue him?