Power Query count occurrences of specific character in column

Hello all

Im would like to add a column to a table, that counts the number of occurrences of the specific character | in another column, like this:
CountOccurrencesInColumn.png


As I understand from this post, I should be able to do this in by adding a calculated column with this:

AllCount = LEN(Tabel1[All])-LEN(SUBSTITUTE(Tabel1[All],"|",""))

But I cant figure out how to actually apply that - if I just write it in the Power Query M code it gives errors.

How can I add this column in Power Query?

Please note that I only have up to 2 occurrences in the sample, but in my actual setup I have more than 150 in some rows.

Best regards
Imbizile