Chop the onion, bell pepper, zucchini, and carrots into 3 inch match sticks. Slice the beef into thin stir fry strips.
Heat a large wok, over medium high. Scoop 1 tablespoon of the coconut solid into the hot pan (use vegetable/peanut oil, if the coconut milk has not separated). Add the curry paste to the pan, and stir until the mixture of coconut solid and paste has thickened (warning: do this in a well ventilated kitchen. I usually gauge the readiness of the paste, by how much I am coughing/crying). Add the meat, and 1/2 of the can of coconut milk. stir together to coat the meat. continue stirring and simmering for about 1 minute before adding in the onion. Continue stirring in the onion until the sauce has thickened, and the meat is well coated. Add the rest of the coconut milk, along with the bell pepper, zucchini, and carrots. Stir the ingredients together, and then cover for 3 minutes. Add the broccoli, and cook for 1 more minute. Add fish sauce just before serving (be sure to taste first).