2. Cut the escarole and the radicchio in quarters, cutting directly through the root end so that each quarter remains intact. Gently wash the lettuce quarters. Using 2 teaspoons of olive oil, sprinkle each quarter head of lettuce with oil and salt.
3. Grill the lettuce quarters on all sides until the leaves just begin to wilt, about 5 to 8 minutes total. Set aside and cool.
4. Toss the grilled lettuces and butterhead with the lemon juice and fresh pepper. Divide the salad among 4 plates and serve.