This is not working because admin-header.php doesn't have Roboto Condensed font.
Why you add styles like input:disabled, select and etc in the admin.css like it can be used only on admin page?
Delete this file media/chana-masala-recipe_684f4743a2a80.jpg. It's don't need in the media folder.
I know that you used it because we don't have image url early, but not this is file isn't…
I think you need to save this file in the ASSETS_PATH like toastify.js.
You can create a new function like get_html_instruction() in the RecipeModel, which returns the formatted instruction (as string).
Days of the week can be used in different places, so it would be better to save them as a constant variable to make them reusable.
Can you create a new function in the RecipeModel that returns a string combining the estimated_time field and the word “minutes”? I think it will be used repeatedly in the future.