Start by placing a medium saucepan over medium-high heat. Add the vegetable oil and let it warm up for a moment. Toss in the chopped onion, stirring occasionally for about 2-3 minutes until they become translucent.

Next, add the beef mince to the pan with the onions. Continue to fry everything together for around 3-5 minutes, ensuring the beef is nicely browned.

Once your beef is perfectly browned, pour in the dashi stock and bring it to a boil. After it reaches that lovely bubbling point, toss in the udon noodles. Let them cook for just a couple of minutes, or a bit longer if they're frozen.

Break up the curry roux into pieces and add them to the pot one at a time, stirring gently to combine. Keep adding until you reach your desired thickness.

Once everything is nicely combined and heated through, ladle the delicious curry udon into bowls while it's still piping hot. Garnish each bowl with chopped spring onions.