During our last visit to Paraguay I bought a motorcycle and had lots of adventures. One of the recurring characters in my advrider story was Hamburguesa Completa - the "complete hamburger." I cook on Tuesday and have spent the past months working on the recipe. It starts with ground beef with diced onions and bell peppers. I add salt and garlic powder and pepper and cumin. The cumin is essential for the Paraguayan taste. It's also an ingredient in many Mexican style spices.
It all gets hand squished in a big bowl and I use a form to compress the mix into patties.