Wash and dry lettuce; chop into bite sized pieces. Wash and thinly slice radishes. If peas are frozen, thaw in a cup of warm water. If peas are fresh, toss in boiling water for 3 minutes, until tender. Zest the lemon.
To assemble the salad, layer the lettuce in serving bowl. Top with radishes, peas and the feta. Sprinkle with lemon zest. Drizzle with dressing.
Lemon Oregano Vinaigrette
Chop oregano. Combine all ingredients in a jar and shake to combine, add salt and pepper to taste.