Combine all vinaigrette ingredients in a blender and puree until smooth.
*To remove seeds from a pomegranate: fill a large bowl 1/2 way with room temperature water. Slice pomegranate into quarters. Hold a quarter under the water and scrape out seeds. The pith should fall to the bottom and the seeds should float, so you can just scoop them up.
Preheat oven to 400 and add walnuts to a baking sheet. Roast walnuts for 10-12 minutes or until fragrant and slightly darker in color. Remove from oven and place walnuts in a heat-proof bowl. Toss with maple syrup and cayenne and spread back onto baking sheet to cool.
Slice off approximately 3/4" of the base of your fennel, as well as the fronds (the things sticking out), leaving just the round bulb. Slice into rounds as thinly as you can, at least 1/4" thick. Rinse and drain and pat dry.
In a large mixing bowl, combine mixed greens, pomegranate seeds, sliced fennel and roasted walnuts. Add goat cheese, if using, then toss with Avocado Oil Vinaigrette to taste.