As far as eating goes I would add more calorie dense snacks like nuts or peanut butter with your fruit, avocado in your salad, oatmeal with cinnamon & raisins or yogurt. Also adding more protein is a must, maybe a protein shake or extra piece of meat will help. Just adding a couple of these a day can make a big difference.
I'm not sure what your workouts look like as far as sets, reps, weight but increasing the intensity with more weight and adding accessory exercises will help. For bench add tricep dips, over head press, rows, any tricep work, etc. For squats add lunges, step ups, glute ham raise, front squats. For deadlifts add hamstring curls, hip thrusts, good mornings, and kettle bell swings. The more intense the workout the more hungry you will be so the extra food wont feel like you're trying to choke it down.