Dry-roast cumin seeds in a skillet over medium-high heat for about 45 seconds until fragrant. Cool.

Dry-roast coriander seeds and Thai peppercorns in the skillet for about a minute until aromatic. Cool with cumin seeds.

Grind the cooled spices in a spice or coffee grinder.

Transfer the ground spices to a large shallow pan, add palm sugar and soy sauce.

Add the sliced beef, stir well to coat, cover, and marinate overnight in the refrigerator.

Place the marinated steak on wire racks and dry in the sun for a day, turning occasionally.

Alternatively, dry in a 150°F oven for at least 8 hours until dry and leathery.

Store in the refrigerator.

To serve, shred and deep-fry in hot oil until crispy.