Big Eye Tuna Tartare

Directions

1. For the Avocado Relish: Mash the avocado flesh with the tines of a fork and add in the lemon juice. Add in the onion and chives. Add in the oil in a stream, stirring to blend. Add in the salt and pepper to taste.
2. For the Green Peppercorn Dressing: Place the peppercorns, their juice, the mustard and the lemon juice in a blender. Add in salt and pepper to taste. Blend at low speed for 30 seconds. Add in the oil in a slow stream, blending on high speed. Taste and adjust the salt and pepper.
3. For Assembly: Slice the radishes as thinly as possible, using a mandoline if you have one. Make a ring with the radishes in the center of each of 4 chilled plates. Place a 2 1/2-inch diameter ring mold in the center of each ring of radishes. Divide the avocado relish among the molds; it shouldn't be more than one-half-inch tall.
4. Season the tuna with salt and pepper. Add in the green peppercorn dressing to taste, about 1 1/2 Tbsp.. Add in the chives and onion. Mix well. Adjust the seasoning. Divide the tuna among the 4 molds and smooth the tops. Remove the molds.
5. Dress the greens very lightly with about 1 Tbsp. of the dressing. Place the greens decoratively over the tuna. Drizzle the remaining dressing around the plates. Serve immediately.
6. This recipe yields 4 appetizer servings.
7. Comments: Green peppercorns are available at specialty markets and well-stocked supermarkets. Big-eye tuna is sold at specialty supermarkets and fish stores. Keep the tuna on ice as you work with it. Metal ring molds can be found at cookware stores and are often sold in sets.