Is the Fire HD 8 too slow for audiobooks and recipes?

Usually, no — the Fire HD 8 should be fine for audiobooks, but it can feel slow on some recipe websites.

Audiobooks: Audiobook apps are generally lightweight, so the Fire HD 8 is usually capable of playing audiobooks without much trouble. If you’re just listening, it should be a workable device for that use.

Recipes: If you’re using a dedicated recipe app or reading a Kindle cookbook, it should be fine. If you’re browsing modern recipe websites in the browser, you may notice lag, especially on pages with lots of images, ads, and embedded media.

If you plan to use it mostly for recipes in the kitchen, a recipe app or a simplified view/reader-style page will usually be a better experience than full web pages.