Place the tofu block on its narrower side. Cut into 8 rectangles about 3/8-inch thick.
To press out excess water, place the rectangles on a towel-lined cutting board and cover with another clean towel. (Use tea towels—the ones without terrycloth nubs.)
Place a 9 x 13-inch pan over the covered tofu. Place something heavy in the dish–I use my blender. After 5 minutes the tea towels will have absorbed excess water, and the tofu pieces will be easy to pick up.
In a bowl, toss the onion rings and fennel slices with the first ¾ teaspoon salt and the first 2 tablespoons olive oil.
Place the pressed tofu pieces in the pan you used to weight the tofu. Sprinkle with the remaining salt and olive oil.
Heat the grill to high (450°F.).
Mix the marmalade, tamari, orange zest and juice in a small saucepan. Bring to a boil, then remove from heat. Set aside.
On a vegetable grill rack with holes narrow enough that the vegetables don’t fall through, grill the onion and fennel until they are soft and have char marks.
Remove from the grill.
Place the tofu on the same grill rack, or directly on the grill if you are sure they won’t fall through. Grill until the tofu is golden on both sides. In the last minutes, brush with some of the jalapeño orange sauce.
To serve, spread the onions and fennel in a serving dish. Arrange the tofu on top and drizzle with the sauce. Garnish with fennel fronds.
Serve with couscous, quinoa or brown rice.
Notes
Use a quality marmalade, one made without corn syrup.