In a heavy pot, add 2 tbsp of olive oil to heat.
When oil shimmers, add half of the chuck roast, searing on all sides. Do not crowd the pot.
Sprinkle salt and pepper over each piece as it sears.
After all sides are seared, remove from pot.
Add another 2 tbsp of olive oil and sear remaining beef and adding salt and pepper.
Remove all beef from the pot.
In the pot, add onions, garlic, lemongrass, ginger, and 5 spice to toast and brown.
After onions start to soften, add ketchup and fish sauce. Mix together.
When mixture starts to boil, return meat to pot and add brown sugar and water.
Mix and simmer on low for 2 hours, skimming any foam as necessary.
For the last 15 minutes, add chopped carrots.
Serve with rice, noodles, or bread!