Place the olive oil and butter in a small saute pan set over medium heat. When butter is sizzling, add green onions, garlic, black pepper, salt and cayenne pepper and sauté, stirring, 15 seconds. Scrape mixture from pan into the riced potato and mix.
Separate smoked salmon into 8-ounce and 2-ounce portions. Remove bones (and any visible fat) from both. Cut 8 ounces of salmon into small pieces and process in a food processor until fine. Mix into the potato mixture until combined. Cover with plastic wrap and refrigerate. Cut remaining 2 ounces of salmon into julienne strips and refrigerate.
Prepare horseradish, tomato and grainy mustard dressing and the wine potatoes and capers. (Potatoes and capers will need to sit in refrigerator at least 2 hours.)
When ready to assemble, divide smoked salmon mixture into about 36 (½-ounce) portions. Form each portion into a 1 ½-inch cylinder.
Lay out the won ton wrappers and place 1 salmon cylinder in the center of each. Brush the outer ½ inch of the wrappers lightly with water. Fold wrapper over the cylinder, matching edges evenly to form a rectangle. Press across the top edge to seal. Stand won tons upright so the top edges are straight up. To seal, press downward on each side of the edge; sides can be wet lightly with water so they seal well. As each kreplach is finished, place it on a parchment-lined tray and cover with plastic wrap until ready to fry.
When ready to serve, place a large pot that has been filled about one third full with peanut oil (to make a deep-fryer) over medium-high heat. Place a deep-frying thermometer in the pot and, when oil reaches 360 degrees, begin frying the kreplach in batches. Do not crowd or they may stick together. When they are golden brown, after 3 to 4 minutes, remove with a slotted spoon to paper toweling to drain. Keep fried kreplach warm on a metal drain tray in a 250-degree oven while finishing frying the remaining kreplach.
Toss the (now drained) wine potatoes and capers with enough dressing to just moisten. Serve kreplach as an appetizer on top of the wine potatoes and capers. Garnish with additional dressing along with the julienned salmon. Kreplach also can be served as an appetizer with the dressing as a dip.
Tester's note: Leftover salmon kreplach can be refrigerated and eaten cold, though they will not be crisp anymore.
Horseradish, tomato and grainy mustard dressing:
1 shallot (1 ounce), peeled, thinly sliced and rinsed under warm water
1 large clove garlic (¼ ounce) peeled, thinly sliced and rinsed
2 tablespoons drained capers
1 egg yolk, room temperature (from a pasteurized egg)
2 tablespoons grainy mustard
1 tablespoon plus 1 teaspoon red wine vinegar
1 ½ teaspoons dry mustard
1 cup grapeseed oil
1 tablespoon tomato paste
1 tablespoon fresh lemon juice
½ teaspoon kosher salt
½ teaspoon freshly ground black pepper
3/8 teaspoon cayenne pepper
3 tablespoons drained prepared horseradish
Kosher salt and freshly ground black pepper to taste
Place the shallot, garlic and capers in a mini food processor and process 5 seconds. Add egg yolk and grainy mustard and process 10 seconds.
In a small bowl, mix the vinegar and dry mustard together.
Start adding 1/3 of the oil slowly to the shallot mixture while processing. Add the dry mustard/vinegar mixture, then the tomato paste, and process until combined. Add another 1/3 of the oil slowly, the lemon juice, salt, the peppers and then the remaining 1/3 cup of the oil. Add the horseradish, taste and adjust seasoning with salt and pepper.
Wine potatoes and capers:
1 pound russet potatoes, peeled and cut into ½-inch cubes
Kosher salt to taste
1 cup dry white wine
¼ cup drained small capers
Cover potatoes with water and enough salt so the water tastes like seawater. Bring to a simmer and cook until potatoes are tender but not falling apart. Immediately drain potatoes and place in a container large enough to hold them in 1 layer. Top with wine and let sit at least 2 hours. When ready to use, drain off the wine and mix in the capers.
