In a small pot, stir together the first 8 ingredients along with several grinds of black pepper. Turn the heat to medium and heat the sauce to a simmer. Remove the pot from the heat and set it aside.

Add a splash of veg oil to a large pan on medium-high heat. Add the pork and let fry for 3 or 4 minutes until it's no longer pink. Use a spatula or wooden spoon to break the meat up as it cooks. Drain all but a few tbsp oil from the pan.

Add the shallot and garlic to the pan of pork and fry 1 minute until fragrant. Add the carrot, red pepper, and zucchini, along with a pinch of salt and pepper. Keep frying until you get some caramelization on the meat and veg. This will take about 5 or 6 minutes. Add 3 or 4 tbsp sauce to the meat and stir to coat. Turn the heat down to low.

Add a small splash of sesame oil to a medium pot of boiling water. Drop in the udon noodles and cook for about 3 minutes, just until the noodles break apart. Drain well. Add the udon to the pan of meat along with half of the sauce, and toss everything together. Serve with the remaining sauce on the side, so guests can add more if they wish.