Whisk jam in large bowl until smooth. Add vinegar, shallot, salt, and pepper and whisk until combined.
Whisking constantly, slowly drizzle in oil until emulsified. Stir in sliced fennel and let sit for 15 minutes.
Add arugula, grapes, and fennel fronds and toss
gently to coat. Season with salt and pepper to taste and divide salad among individual plates. Serve, topping individual portions with blue cheese and pecans.
