Preheat the oven to 350 degrees. With a biscuit cutter or heart shaped cutter, cut out heart shapes (can be done in advance). Brush melted butter on both sides of the bread and set them on a baking sheet. Bake for 15 minutes or until toasts are golden brown; remove and set aside until later. (Or, for low cal alternative, cut wide thin slices of jicama, then cut out heart shapes from those - can be done in advance, and kept in dampened cloth in the refrigerator.) Combine olive oil and lime juice and season lightly with salt and pepper. Set two "heart" shaped toast points or jicama slices in middle of a dinner plate. Heart points should meet in center and overlap each other slightly. Roll up or drape a slice of smoked salmon in the middle of each heart and brush with olive oil and rice vinegar dressing. For a professional looking presentation, scatter dill and chives over everything; including the plate. At last minute, coarsely grind fresh pepper over the top.