To make the dressing, zest the lemon first and place the zest into a large measuring cup. Squeeze in the lemon juice next.
Pour in the olive oil and add the maple syrup, Dijon mustard, whole grain mustard, thyme, salt, and black pepper. Use a zester to grate the garlic and add it to the cup.
Whisk all the ingredients vigorously, then set aside until ready to use.
Preparing the Salad Ingredients:
Fill a large bowl with cold water and add a few tablespoons of baking soda. Submerge the entire head of frisée lettuce for a few minutes and swirl it around to clean. Do two additional clean rinses, then shake the lettuce dry.
Cut off the end core/browned bottom from the head of lettuce, then chop the frisée into serving size pieces. Place the lettuce into a large serving bowl.
Next, prepare the pears. Slice them in half, remove the core, then slice thinly using a sharp knife or mandolin slicer.
Slice the shallot thinly into rings. Dice the salted pistachios. Chop the dates into small, pea-sized pieces.
Assembling the Salad:
Sprinkle the sliced shallots over the frisée lettuce. Arrange the pear slices into fans, about 5 to 6 slices in each bunch, then add the pears over the lettuce.
Sprinkle the diced pistachios and chopped dates over the top. Crumble the blue cheese and sprinkle evenly.
Give the salad dressing a quick whisk and pour over the salad. Add the salad dressing right before serving; otherwise, keep it on the side!
You can prepare the salad up to 4 hours ahead of time. Simply keep the salad covered and refrigerated. To keep the pears from browning, brush them lightly with lemon juice.