Tempura oysters with hair moss & red pepper wasabi mayonnaise

Few dishes are as emblematic of Chinese New Year as Fat Choy Ho See—Braised dried oysters with Hair Moss—which portends prosperity in all business affairs. This is an updated twist on the traditional.
Ingredients: 
12–18 medium oysters, shucked
2 slices fresh ginger root
1 green onion, smashed
1 cup / 250 mL tempura batter
1 Tbsp / 15 mL cornstarch
1/4 cup / 180 mL cold water
2 ice cubes
2 cups / 500 mL canola or vegetable oil
2 Tbsp / 30 ml dried hair moss, soaked in enough hot water to cover
pinch sugar & salt
salt & pepper to taste
1/2 cup / 125 mL mayonnaise
1/4 cup / 60 mL pureed roasted red peppers or pimentos
1 lemon, juice and zest
1/2 tsp / 2.5 mL wasabi powder, or to taste

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Red Pepper Wasabi Mayonnaise: In a small bowl, combine mayonnaise, red pepper puree, lemon juice and zest and wasabi and mix well. Season with sugar and salt to taste. Cover and refrigerate until ready to use.

 

Bring 2 quarts (2 L) of salted (1 Tbsp or 15 mL) water to boil. Add ginger and green onion. Blanch oysters, in batches if necessary, for about 2 minutes or until they are just firm. Transfer them with slotted spoon onto paper towels. Pat them dry and season lightly with salt and pepper. Drain hair moss; pat dry; and chop finely. In a mixing bowl, combine tempura batter mix, cornstarch, water, ice cubes and hair moss and gently stir to mix. Do not over mix, it should be a bit lumpy. Heat oil in wok or small saucepan to about 360°F (180°C). To test the oil, drop a little drizzle of batter into the oil and if it bubbles and floats to the top straightaway then the oil is ready. Dredge oysters in batter and fry, in batches if necessary, until golden. Transfer onto a rack to drain, then onto a serving plate lined with parchment paper and serve with Red Pepper Mayonnaise on the side as a dip. Serves 4