1. To prepare salmon, clip a kitchen thermometer onto side of a 10-inch skillet. Add oil, basil leaves, lemon slices, and garlic to pan; heat to 150°. Add fish to oil; cook for 12 minutes or until desired degree of doneness. Remove fish from oil; place on paper towels to drain. Sprinkle with 1/4 teaspoon salt and 1/8 teaspoon pepper.
2. Toss cucumber with 1/8 teaspoon salt and 1/8 teaspoon pepper; set aside.
3. Combine juice, chopped basil, remaining 1/8 teaspoon salt, and remaining 1/8 teaspoon pepper in a small bowl; drizzle over fish. Serve with cucumber salad. Garnish with basil leaves, if desired.