Steaming is essential for gently heating the egg base of these Thai-inspired savory custards, which are laced with lemongrass and ginger. Serve them as first courses or light main courses with sliced toasted baguette.
Bring coconut milk, lemongrass, ginger, and cilantro to a simmer in a small saucepan over medium-high heat. Remove from heat; let stand 1 hour.
Pour through a fine sieve into a medium bowl; discard solids. Whisk in egg yolks, salt, and pepper. Ladle into four 8-ounce, 2-inch-high ramekins. Divide crabmeat evenly among ramekins; sprinkle each with 3 or 4 cilantro leaves.
Fill a large pot fitted with a round wire rack or a steamer insert with enough water to just come up to rack. Bring water to a simmer over medium-high heat. Carefully place ramekins in steamer; cover pot. Steam custards over medium heat, checking occasionally to make sure water doesn't completely evaporate, until just set, 18 to 25 minutes. Place each custard on a saucer. Serve immediately with crisp toasts or crackers.