Practice edge control and unmixed watercolors.
Lesson Objectives: Practice edge control. Use unmixed colors such as lemon yellow, Hansa yellow, Cadmium red, orange, sap green and burnt sienna. Also, cobalt blue and perm rose, or alizarin crimson for the shadows. There is more than one approach to starting a watercolor painting. In this case I have painted directly wet on dry without mixing colors in my palette.
Step 1: Using the photo reference draw and shade the peppers to make a values study on regular paper. Draw the outline of the peppers and the highlighted areas. You can trace the outline of the drawing or do it again on watercolor paper when you are ready to paint. Paint the shadow first, wet into wet with a mix of cobalt or ultramarine blue and rose or alizarin crimson.
Step 2: Start with the yellow pepper and paint each section of it observing the values study, and save the whites. Start with the lemon yellow and create shadows with a warmer yellow and either a touch of orange or burnt sienna. You may want to brush clean water first and paint wet into wet. Avoid hard edges, except in the outline, by softening them with the tip of your round brush and clear water. If you paint over a highlight, quickly lift the paint with a tissue.
Step 3: Paint the red pepper. Start from light to dark. Save the whites. Soften the edges within the highlights. I used cadmium red and a deep orange. Follow your values study. Make sure you separate each section of the pepper with tone. Think light and dark. Paint the orange pepper following the same technique.
Step 4: Paint the stems with the light coming from the left. Soften the highlights of the red and orange peppers by pulling the color around them with the tip of your clean and barely wet brush.
Step 5: Sprinkle with olive oil and chopped rosemary. Roast them at 400-450F for 30-45 minutes. And call it a day!