Hey @Frederic! Welcome to the community.
Here’s a walkthrough on how you can achieve this using Parabola. This assumes you have a separate list of keywords and tags that you can import.
Start by importing your keywords/tags and recipes. Here’s what my recipes data looks like:
And here’s what my keywords data looks like:
Using two Insert Text Column steps we can create new columns for each table called Join and insert a value of 1. This new column will eventually be used to merge the tables together.
I like to reorder the columns, but it’s a personal preference. This won’t affect your flow. We’ll now use a Combine tables step to join on the matching Join column.
This will create duplicate rows, but we’ll take care of that later. We’ll use an Insert if/else column. Don’t worry, it will only require one rule. 
Let’s create a new column called Keyword?. If a recipe contains a keyword in the same row, the value Yes will be inserted in that column. Otherwise, the value is blank.
Lastly, we can use a Filter rows to show rows that have a value of Yes in Keywords? column. The resulting table should show us a list of recipes, keywords, and tags associated with those keywords.
Let me know if that helps!