First get the sauce on. Use a large frying pan, the one you will finally break the eggs into. Finely chop the garlic and let it sizzle (don't let it brown) in the oil over a medium heat. As soon as it starts to colour tip the tomatoes in. Salt. Let it simmer for 35 minutes with lid on. Keep stirring to avoid sticking.
Meanwhile, squeeze meat from cooking chorizos. Grind cumin in a pestle and mortar or with back of spoon, or a little blender. Or don't bother if you don't have the tools. Fry off in a dry pan for a few minutes until a bit smoky. Then add chorizo mince. You will have to squash it and break it up with a wooden spoon. Let it fry until crispy, about 20 minutes on a medium heat. Turn off heat and set aside till needed.
When the sauce is done, add spinach and stir till wilted, a couple of minutes is fine. Break eggs into the pan. and put lid back on.
When they are almost done, but still looking wobbly - I like my yolks runny - sprinkle with crispy chorizo.
Serve in the pan at the table, with crusty bread and maybe some fresh coriander too.