Step 1

Heat a medium skillet over medium. Add fennel seeds and cook, stirring often, until toasted and fragrant, 3 to 4 minutes. Transfer to a cutting board. Using the bottom of a measuring cup or bowl, lightly crush seeds.

Step 2

Heat 1 teaspoon oil in same skillet over high. Add radicchio wedges and cook, flipping once, until softened, 2 to 3 minutes per side. Transfer to a cutting board and let stand until cool enough to handle, about 5 minutes. Remove and discard core; chop radicchio into 1-inch pieces.

Step 3

Whisk crushed fennel, vinegar, mustard, and salt in a large bowl. Whisk in remaining ¼ cup oil.

Step 4

Add farro, pear, arugula, and radicchio to bowl and toss to coat. Divide salad among plates and top with tuna.