How would you grow this?
I created a paid group about Vietnamese food. (one of my favorites). https://groupsalternative.com/vietnamese-food-group
Thanh, our community manager from Saigon is an expert making Pho-Bo and the traditional dishes of the Vietnamese cuisine.
We charge $2 a month to be part of the group, make questions, posts, etc.
The big question is, how do I grow it. How do I make enough of the right people see it? Maybe I could try to sponsor a related Newsletter.
You could try running instagram advertisements. The facebook ad platform allows you to target different audiences very granularly. So you can run experiments and test ads against a number of different audience and see which perform best.
I'd also recommend posting to relevant subreddits.
+1 to this. Where do your potential customers live? Sub-reddits are a good start. You can search all of Reddit to find if and where people are talking about Vietnamese food.