For beginners, arranging the food on the plate is an easy start. We eat with our eyes. Colorful analogous arrangements of food demand our attention much more than monochromatic ones. Expectations of taste are higher with visually appealing food.
About half of the brain's cortex relates to the visual. Only a small percent of the brain is concerned with taste.
Anyone can make a meatloaf with a "surprise" hard boiled egg center. Red sauce and greens are easy additions.
Color in meals should be should meet the eater's expectations. The bounty of summer fruits and vegetables will add bright oranges, greens, reds, yellows and enjoyment to any meal. Blueberries aside, blue food is the least appetizing.