My Grandmother used to make a cake at Christmas time and she called it "Ambrosia cake". It was spicy and dark with lots of nuts & the frosting had ora

Ambrosia cake is a Southern USA dish. (Was your Grandmother from the South?) Google finds lots of recipes, but those that had nuts didn't have oranges, and those with oranges, didn't have nuts. You could swap and adjust to taste so your version had both.
See this search and especially the recipes from Serious Eats, Epicurious, NY Times.
https://www.google.com/search?q=best+ambrosia+cake+recipe&oq=ambrosia+cake+recipe&aqs=chrome.4.69i57j0l7.8535j0j7&sourceid=chrome&ie=UTF-8