In a small bowl, stir together the shallot with the mustard, lemon juice, and vinegar. Slowly pour in the olive oil while whisking the ingredients together. Season with salt and pepper and whisk to combine.
For the Salad
In a large bowl, layer the arugula with the fennel and tomatoes. Drizzle some of the dressing over this salad base.
On top of the dressed greens, sprinkle on the microgreens, parsley, and pine nuts. Season the entire salad with a pinch of salt and some cracks of fresh pepper.