Seir

The story

Seir Restaurant in Kasterlee, Belgium – Modern French Cuisine by Chef Thomas Van der Flaas

A Chef’s Dream Realised in the Kempen

Chef Thomas Van der Flaas began his career at Fleur De Sel, followed by a short stint at the three-Michelin-starred Quique Dacosta in Alicante, before realising his dream of opening his own restaurant. Seir opened its doors in the summer of 2018 in Kasterlee, Belgium, with early mentorship from Alex Verhoeven of Hert*. Today, the chef runs the kitchen entirely autonomously. His partner, An-Sofie De Ridder, welcomes guests as hostess and sommelier, ensuring a warm, attentive experience from start to finish.

Modern French Menus with Character

The restaurant’s name, a play on the Flemish word for a glass veranda or greenhouse, hints at the atmosphere: transparent, inviting, and full of life. The cuisine is modern French, built on local products and a clear, stubborn vision. Diners choose from a Chef’s Menu, a Menu Seir, or à la carte. The current feestmenu (festive menu) offers a progression of dishes such as Cappuccino of shrimp, Mackerel – Dashi, Goose liver – Algae, and Polenta – chicken liver, followed by mains like Turbot with North Sea crab, Gnocchi with truffle and Paleta ham, and Pheasant with quince and witloof. The kitchen accommodates allergies and intolerances, though vegan options are not available.

Recognition and Atmosphere

Within its first year, Seir was noticed by Gault&Millau, and later received a score of 15/20 in the same guide. More recently, it earned a Michelin Recommended distinction, a nod to the restaurant’s consistent quality and character. The setting is described as gezellig (cosy) and accessible, with outdoor seating and air conditioning. The cuisine is defined by tension, flavour, and a touch of stubbornness—all served with a smile.