Tasty Recipes supports adding images to the description, ingredients, instructions, and notes fields. To do so, simply click the image button in the editor:
Tip: If you are adding an image to a list and you do not want the image to be its own item (eg. you don't want the image itself to be step 3 of the instructions), press Shift+Enter to put it on a new line but not as a new item.
If you want to read up on image sizing best practices you can check that out here.