One of the tricks that professional chefs have is to give thematic unity to a seemingly disparate ensemble.
The dish below is an example of that.
The cod has been crusted with a mixture of hazelnuts, breadcrumbs, thyme and lemon zest.
The potatoes have been roasted with harissa, olive oil and thyme.
The vinaigrette for the salad in the background is made with lemon juice, thyme and hazelnut oil.
As you can see there's a clear thematic element of lemon, hazelnuts and thyme running through the ensemble.
There is also a clear visual and methodic disparateness. Textures, colors, cooking methods all separate to provide interest but tied into an integrated whole at an underlying level.