Most people consider tamarillo skin unpleasantly bitter, so you should either peel the fruit before eating/cooking it or simply scoop the flesh out of cut halves are you would a kiwi fruit.
While you can use a vegetable peeler, the recommended way to remove tamarillo skin is to first loosen it by soaking them in boiling water for three to four minutes. Drain the hot water and recover with cold water, peeling them by hand under the surface.
Some South American cultures use sweetened tamarillo puree as a base for refreshing drinks. They can also be pickled (particularly gold tamarillos), roasted, grilled, poached in sugar syrup or turned into jams, sauces, and marmalades.
Tamarillos pair well with savory tomato-friendly flavors like basil, oregano, avocado, onions, garlic, and fresh peppers. To use them as a fruit in desserts, pair them with flavors like cinnamon, star anise, honey, orange, cream (particularly ice cream), brown sugar, and mint.
Note: Tamarillo juice can stain, so don’t cut them on wood cutting boards and avoid getting it on your clothing.