Fill a large bowl halfway with ice and water then set aside. In a medium saucepan over high heat, bring 1-inch water to a boil. Place the broccoli in a steamer basket and place over saucepan. Cover, reduce heat to medium-low and cook until broccoli is bright green, about 4 to 6 minutes.Drain well and transfer to the bowl with ice water to cool for about 10 minutes. Drain again then transfer to a salad spinner and spin dry (or lay on a towel to dry).In a blender or food processor (I used a NutriBullet) combine avocado, olive oil, lemon juice and zest, garlic, and 3/4 teaspoon salt + 1/4 teaspoon pepper. Blend until smooth, about 30 seconds, scraping down sides of bowl as needed.Add broccoli to a large serving bowl then add the avocado dressing, cranberries, almonds, shallot and tarragon. Toss to combine then season with salt & pepper, to taste. Serve immediately and enjoy!