Add olive oil, vinegar, honey, salt, and pepper to a shaker bottle or small mason jar. Shake to combine and set aside. Alternatively, whisk contents in a medium bowl.
Arrange citrus segments, sliced avocado, and fennel on plate. Drizzle with dressing, and top with fennel fronds. Serve immediately.
I know segmenting citrus is not a fun job. You can skip this step if you don't mind eating the membrane and/or don't have time. Bonus - use the leftover salad ingredients to top a green salad the following day. This goes great with arugula and grilled chicken. Be sure and use extra dressing so it doesn't eat dry.