It’s easiest to do this in batches, cooking one egg at a time in a small frying pan. If you don’t have a pan small enough, you can try cooking all of the eggs in one pan by sectioning them off into 4 sections of the pan.
Heat a small nonstick skillet over a medium-heat. Crumble ¼ feta into the pan, placing it around the outside and leaving room for the egg in the centre. Add about 2 small spoonfuls of the baked beans into the pan and spread them out so that they’re evenly distributed in the pan - you don’t want too much as it will overfill and spill out of the taco. Once the feta and beans start to melt and bubble, crack an egg into the centre and season with black pepper (the beans + feta are salty enough). Cover the pan and cook for 3 minutes, until the white is set, the yolk is still runny, and the cheese is golden. Repeat this for all 4 eggs.

Meanwhile, warm the tortillas in the microwave or dry pan to slightly char it. Scoop out ¼ of the avocado onto the tortilla and mash with the back of a fork to cover the base of the taco - add a squeeze of lime juice. Using a turner, carefully scoop the feta egg from the pan and glide it onto the taco.

Garnish with some fresh coriander and finish with an extra squeeze of lime, plus some chilli flakes, if you like it extra spicy.