In a large, dry skillet over medium-high heat, toast cashews until golden brown, about 5 minutes. Remove cashews to a dish to cool slightly.
Return skillet to medium-high heat, cook bacon strips until crisp on both sides, about 7 minutes. Remove bacon with a slotted spoon, and soak up grease with a paper towel. Coarsely chop bacon, and set aside.
In a medium bowl, stir together butter, rosemary, curry powder, brown sugar, salt, cayenne pepper, and toasted cashews. Set aside.
In a small bowl, stir together white wine vinegar, mustard, and honey. Slowly whisk in olive oil, and sprinkle with salt and pepper to taste.
In a large salad bowl, toss dressing with greens, pear slices, grapes, and bacon, and sprinkle with nut mixture.