De Kas is a restaurant in an actual greenhouse in Frankendael Park, which is either brilliant or completely over the top, depending on your mood. But here's the thing: it works.
They grow their own vegetables, herbs and flowers around the restaurant. What's in the ground in the morning is on your plate at lunch. The menu changes with the seasons because it has to, not because it's marketing. This is farm-to-table without the pretension, simply because the farm is literally next to your table.
The menu is short. Tight. Exciting. You get what's ready, what's good, what's growing. And that's exactly enough. It's perfect for those long lunches where you forget you actually have things to do, or a quiet dinner where you can finally talk normally without shouting from other tables.
Is it expensive? Yes. Is it worth it? If you love truly seasonal food and aren't waiting for the umpteenth place claiming to be 'local' while buying their vegetables from wholesale - then yes, absolutely.