Pat the beef chuck pieces dry with paper towels and season them lightly with salt and pepper. Heat the vegetable oil in a large Dutch oven or heavy-bottomed pot over medium-high heat.

Sear the beef pieces in batches until a deep brown crust forms on all sides, about 5 to 7 minutes per batch, then transfer the seared beef to a plate and set it aside.

In the same pot, reduce the heat to medium and add the chopped onion and minced garlic, sautéing for 3 to 4 minutes until the onion is soft and translucent while scraping up the browned bits from the bottom.

Return the beef and its juices to the pot, then pour in the soy sauce, lemon juice, tomato sauce, brown sugar, star anise, bay leaves, and beef broth, stirring well to combine.

Bring the mixture to a boil, then reduce the heat to low, cover the pot with a tight-fitting lid, and simmer gently for 60 minutes until the beef begins to turn tender.

Stir in the cubed potatoes, cover again, and continue to simmer for an additional 20 minutes, or until the potatoes are fork-tender and the sauce has thickened into a rich, glossy glaze.

Discard the star anise and bay leaves before serving, then ladle the hot beef asado over warm, steamed jasmine rice and enjoy.