Query many-to-many relationship in Prisma

Question

I want to query a many-to-many relation in prisma, like "select all posts where the category ID equals 'abc...' ".

This seems fairly simple but even after spending 2 hours reading the Prisma docs on relational queries, I can't figure it out.

model Category {
  id               String    @id @default(cuid())
  name             String
  post             Post[]
}

model Post {
  id               String    @id @default(cuid())
  body             String
  category         Category[]
}

const posts = await prisma.post.findMany({
      select: { 
        category: {
          where: {id: "abc123"}
        }},
    });

this returns an array of as many category objects as there are posts.