Temperature and time keys. To bake salt and pepper walnuts in the oven, select the temperature and time buttons, the upper and lower heat modes, and the temperature can be 130 to 150 degrees. The time is 15 minutes. Spread aluminum foil on a baking sheet (you can use oil paper or oilcloth), spread the cooked walnuts on the baking sheet, and sprinkle with white sesame seeds. Once it reaches the preheated temperature, place in the oven.