For Seasoning Salt:
Grind allspice, fennel seed, pepper, and salt in a spice grinder
For Tomato Jam:
Place tomatoes, vinegar, and sugar in a non-reactive pot and cook until thick. Season with and Seasoning Salt.
For Green Goddess Dressing:
Combine tarragon, egg yolks, avocado, garlic, and vinegar in processor and blend. Slowly add peanut oil to form an emulsification. Season with salt and pepper, and a little lemon juice to brighten up the dressing.
To Assemble and Serve:
Toast buns on the griddle till golden brown. Form turkey into a ball and season with Seasoning Salt. Heat some canola oil on the griddle and press the balls into patties with the back of a spatula. Cook turkey on first side till dark golden-brown, then flip. Cook all the way through.
For each burger, spread the Tomato Jam on the bottom of the toasted bun and the Green Goddess Dressing on the top. Place patty on the bottom bun, top with arugula and close the sandwich.