Mani's Cafe and Bakery has been around for years; Mani is no longer the owner, but his recipes live on and like any good thing, they thrive because they are good. From their Fairfax location, you can even order online and get your breakfast or lunch delivered.
I like their Santa Monica location with it's outdoor patio and location 1 block from the beach; all this means that if you would like an easy beach day, just order your lunch at Mani's to go and walk over to the sand a block away to enjoy a beach view with your meal. I love their gourmet salad with freshly grilled shrimp, candied walnuts, and blue cheese. If you want a splurge, go for one of their pastries for dessert, you can't go wrong with a carrot cake muffin or a blueberry tart. They always have a stand at the Sunday Farmer's Market on Main Street, so if you are awake before noon on a Sunday, head over to their stand and sample their croissants while listening to the live music in the park.
It may not be Chicago, or Saturday, but Sunday in the park, with good food and good music is almost as good as the Fourth of July.