For the Dressing: In a large bowl, whisk all ingredients together until an emulsified dressing forms.
For the Salad: Add mesclun, red and green bell peppers, and sundried tomatoes to the dressing bowl and toss to coat.
Gently toss avocado with dressed mesclun.
Season to taste with salt and pepper.
Transfer to a large serving platter (or leave in large serving bowl).
Top with crumbled goat cheese and walnuts.
Serve.
