In a bowl, whisk together the hot water, salt and sugar until dissolved. Stir in the rice vinegar. Toss with the sliced cucumber. Refrigerate while preparing the rest of the recipe or up to overnight.
MAKE THE BLACK PEPPER SAUCE:
Heat the oil in a large saucepan over medium heat. When the oil is shimmering, add the garlic, ginger, shallot, and lemongrass and cook, stirring until the vegetables are softened but not browned, about 2 minutes.
Add the pepper and cook, stirring, until fragrant, about 2 minutes.
Pour in the coconut milk, hoisin, vinegar and fish sauce. Stir, bring to a boil and then lower the heat and simmer for 15 minutes to develop the flavor. Stir in the lime juice. The sauce can be refrigerated in an airtight container for up to 3 days.
GRILL THE SHRIMP (while the sauce is simmering):
Heat a grill to high. Brush shrimp with the cooking oil, season with salt and pepper. Grill shrimp 2 minutes, flip and grill an additional minute or two until cooked through.
Serve with black pepper sauce, pickled cucumber and rice.
Notes
Recipe adapted from Harold Dieterle, Harold Dieterle's Kitchen Notebook Reprinted with permission.Here are some tips for the Black Pepper Sauce:-Instead of mincing ginger, I peel the ginger and grate it with a microplane grater.-If you can't find lemongrass, use a microplane grater and lightly rub the lime in the recipe (before juicing) to zest.-A great substitute for shallot is red onionShrimp tips:This basic recipe can be used for shrimp, fish, scallops and even lobster. I like to use the largest shrimp I can find, and thread on bamboo or metal skewers to make easy to grill.Serve with white rice if desired.