Prepare the homemade ranch dip by combining sour cream, mayonnaise, dried parsley, dried dill, garlic powder, onion powder, salt, pepper, and a splash of lemon juice in a bowl. Stir until well incorporated.
Wash all vegetables thoroughly under cold running water. For added cleaning power, add a splash of vinegar to the washing water.
Cut bell peppers into strips approximately 1/2 inch wide, removing seeds and membranes.
Slice cucumber into 1/4-inch rounds. For regular cucumbers, consider creating a decorative edge by running a fork down the sides before slicing.
Prepare carrots by peeling and cutting into sticks about 3 inches long, or simply open your bag of baby carrots.
Cut broccoli and cauliflower into bite-sized florets, ensuring no piece is larger than two bites.
Arrange your serving platter and place the dip bowl in the center.
Arrange vegetables in a rainbow pattern radiating from the center, grouping colors together: red (tomatoes, red peppers), orange (carrots), yellow (yellow peppers), green (cucumber, broccoli, snap peas), purple (purple cauliflower if available).
For added visual interest, create height variation by leaning some vegetable pieces against the dip bowl or slightly stacking certain vegetables.
Keep refrigerated until approximately 30 minutes before serving to maintain maximum freshness.