Chicken hearts (available at your local butchers) are marinated, skewered and cooked on the barbecue. This typical Brazilian barbecue dish is found in restaurants throughout the country.
Also called achiote powder, it can be found at Asian or Latin American shops and markets, or online. Annatto is mostly used for the vibrant colour it imparts, so in a pinch you could either omit it from the recipe or use equal parts paprika and turmeric instead.
I always stick to the recipe I'm reading, or else it's NOT that recipe a'tall. This was soo bloody good. I'm British, & yes, I CAN cook & bake, & Chicken hearts are a favorite of mine. This recipe was excellent. Thank you ever soo much. Gracias! Cheers From N.V. - 04 Jun 2018 (Review from Allrecipes USA and Canada)