Count how many posts have a specified tag AND category


I know how to count how many posts has a certain tag, or category

For example:

$  term_slug = 'some-post-tag'; $  term = get_term_by('slug', $  term_slug, $  post_tag); echo $  term->count; 

BUT! Is there anyway to count how many posts that have a tag AND a specified category?

I want to count how many posts that have the tag(slug) “cats” and the category slug “allow-list”

Is this even possible?