Step 1

1 Peel the onion and cut it in half, then into very thin half-moon slices

Step 2

2 Coarsely chop the choy sum stems, to yield at least 2 cups

Step 3

3 Reserve the leaves for another use, if desired

Step 4

4 Whisk the eggs lightly in a medium bowl

Step 5

5 Crush enough of the bouillon cube to yield 1/2 teaspoon, then add it to the bowl, along with the sugar and salt, whisking to incorporate

Step 6

6 Heat the oil in a medium nonstick skillet over medium heat

Step 7

7 Once the oil shimmers, add the onion and stir to coat

Step 8

8 Cook for about 5 minutes, stirring once or twice, until softened

Step 9

9 Distribute the choy sum evenly over the onion; cook for about 3 minutes, then gently pour in the egg mixture, tilting the pan so the egg runs evenly around the vegetables

Step 10

10 Use a wooden spatula to stir the eggs once around the pan, then cook for 2 or 3 minutes, undisturbed, until browned on the bottom and the edges are set

Step 11

11 Use the spatula to cut the egg foo yong in half, then turn each half over

Step 12

12 Cook for a minute or two, until lightly browned on the second side

Step 13

13 Divide between individual plates; serve right away