Recipe website redesign – New theme – Help needed

Hi, and thanks in advance for reviewing this request

This is my website https://www.recepti-kuvar.rs/

A recipe website, with 350+ recipes and 100+ registered users submitting new recipes every day (1000+ website visits daily)

We are using a “Food Recipes” theme from Envato marketplace on our website: https://themeforest.net/item/food-recipes-wordpress-theme/1923882

The theme has very low flexibility, we are very limited by it, which is exactly the opposite to the idea of wordpress and the ability to customize everything. We can no longer match our customers’ and potential marketing clients’ and partners’ requests and demands using that theme, so we need to change it.

The problem is that the theme uses a bunch of integrated code and shortcode for submitting and posting recipes. For example, recipes on our website aren’t categorized as “Posts”. They are a custom post type called “Recipe” (that, by the way, conflicted with many plugins thus far).

Also, every single recipe is created by entering 2 shortcodes into wordpress editor: [ingredients] and [method]

My question is: Which is the best way to change to a new theme we selected (https://wpthesisskins.com/newszinedemo1/ skin using a Thesis framework), so ALL recipes and users etc remain as is, without manually editing 350+ recipes to change [ingredients] and [method] shortcodes into actual ingredients and method

Kind regards, and once again thanks

Dejan