Preheat the oven to 300 degrees F.
Slice the pears in half lengthwise. Rub each half with a pinch of salt. Put parchment paper on a tray just large enough to hold the pears, and spread the sugar on the paper. There should be a 1/8-inch layer. Put the pear halves cut side down on the sugar and bake for 1 hour. When the pears are cool enough to handle, remove the cores and slice them crosswise into 1/8-inch sections.
Put the lemon juice in a salad bowl with salt and pepper and mix to dissolve the salt, then whisk in the oil. Arrange the slices of pear 1 pear per plate, in 1 layer in the center of the plate, leaving a 3-inch gap in the center for the watercress and the rocket. Scatter the cheese and then the walnuts over the pears, and then drizzle the honey on top of the walnuts and cheese.
Put the watercress, rocket, and basil in the salad bowl and toss together. Then place the salad in the center of the pears.
Garnish with the flowers.
Recipe courtesy Jeremiah Tower, Jeremiah Tower Cooks, Stewart Tabori and Chang, 2002