Melt the coconut oil in a large skillet over high heat. Sear each steak for 5 minutes per side and then continue cooking until desired doneness. Allow them to cool then cut into strips.
Meanwhile, prepare dressing: To a large food processor, add the next 6 ingredients (salt and pepper through olive oil); blend until smooth.
In a large bowl, toss together arugula, spinach and romaine. Then toss in strawberries and cucumbers; arrange mixture evenly on dinner plates. Top with steak strips and drizzle with dressing.