1. To make the oil: Put the chiles, allspice, clove, fennel, mace, anise, and cinnamon in a large dry skillet and set over medium heat. Cook, stirring occasionally, until fragrant and toasted, 2 minutes. Transfer the toasted ingredients to a blender or spice grinder with the salt and blend until finely ground.

2. Transfer the mixture to a small saucepan and cover with the oil. Set over medium-low heat until very warm, then remove from the heat and cool completely. Strain the oil through a fine-mesh sieve into a container and set aside at room temperature to use immediately, or cover and refrigerate until ready to use.

3. To make the marinade: Put the sugar, lime leaves, and lime juice in a small saucepan. Set over medium-high heat and bring to a boil, stirring occasionally. Remove from the heat and cool to room temperature, then strain the lime syrup through a fine-mesh sieve and set aside.

4. Put the ginger in a blender and blend, adding the olive oil in a slow, steady stream through the feed tube, until the mixture becomes a smooth purée. Transfer to a medium mixing bowl and stir in the vinegar, soy sauce, and reserved lime syrup and set aside.

5. Cut the tuna into strands lengthwise, ¼ inch thick, so that the cut pieces resemble thick linguine. Place in a bowl. Season lightly with salt, then gently toss with the chile, shallots, and 1 tablespoon of the olive oil. In a small bowl season the avocado lightly with salt, then toss gently with the lime juice and the remaining 1 tablespoon olive oil. Season the radishes lightly with salt, then toss gently with half the reserved chili oil.

6. Divide the avocado among four serving bowls and decoratively arrange half the radish slices, then half the tuna strands on top. Stack the remaining radishes and tuna on top, and spoon the ginger marinade around the dish and drizzle the remaining chili oil all around. Serve immediately.