Gently smack cucumbers with a rolling pin or the bottom of a heavy pot until they begin to break apart. Tear into bite-size pieces.

Heat oil in a large cast iron over high heat. Add beef and break apart using a wooden spoon and season with salt and pepper. Cook, undisturbed, until bottom side is browned and crisp, about 5 minutes. Break up meat with a spatula and stir to cook the other side, about 5–7 minutes more.

Add the garlic, red pepper flakes, sambal and Fresno chiles to the beef and cook until fragrant, about 2 minutes. Add shallot and smashed cucumbers and cook, tossing occasionally and scraping up any browned bits, until cucumbers are softened and translucent, about 4 minutes. Remove skillet from heat and stir in vinegars, water, soy sauce, and sugar. Reduce heat to medium and cook, stirring, until sauce is reduced slightly, about 3-4 minutes. Season with salt and pepper to taste.

Spoon beef and cucumbers over bowls of coconut rice and top with herbs and lime wedges.

Place the water, coconut milk, sugar and salt in a medium saucepan, and warm over medium-high heat until the mixture starts to simmer. Add the rice and bring back to a low simmer. Cover the pot with lid, then reduce the heat to low. Cook, undisturbed, for about 15 minutes, then turn off the heat and let the rice steam for another 5 to 10 minutes. Uncover, fluff, and season with the zest and juice of 1 lime.