Eating around Mount Barker is a logistics problem before it is a cuisine problem. You are in a small Great Southern town with a highway, a set of rural cellar doors that may or may not serve food, and picnic sites in a national park that provide barbecues but not a kiosk. Plan the meal as carefully as the walk.
The old site kept /food.html, /food_restaurants.htm, and /cafes_restaurants.aspx. Those pages mixed names and claims this rebuild will not repeat. Restaurants open, close, change cooks, and change days. A static guide that lists them as if they were granite is how travellers arrive to a locked door.
Town first
If you need a reliable meal, start in Mount Barker and confirm on the day. The Shire’s visitor notes mention restaurants and tea rooms as part of a typical district day without turning them into a directory. That is the right level of certainty for a planning site. Ask the railway-station visitor centre, look at a premises that is physically open, or use a current local listing you can verify with a phone number.
Do not assume Sunday hours. Do not assume a kitchen after a late walk. Self-catering accommodation exists in the district for this reason.
Picnics in the park
Parks and Wildlife provide gas barbecues at Tree-in-the-Rock and Castle Rock picnic areas, free to use, with toilets, including facilities designed for people with disabilities. Wood fires are not allowed. There is no drinking water in the park. A picnic is therefore something you pack in town: water, food that does not need a shop at the trailhead, and a plan for rubbish.
A picnic is often a better “food experience” than an unconfirmed cellar-door lunch, especially if the reason you came is the karri forest.
Wine and food are not the same booking
Some Great Southern producers serve food. Many do not. Regional writing talks about cellar doors and tastings; it does not entitle this guide to invent a matching menu. If you want wine with lunch, ask the producer whether food is offered that day, or buy food in town and keep tasting and eating in separate places.
Alcohol and granite walking do not share a morning well. Eat, walk, then taste — or taste on a day you are not on Castle Rock.
Dietary needs
Rural Western Australia is not a city of specialist kitchens. If you have a medical dietary requirement, self-cater and shop in town before you drive east to the range. Do not rely on a single café remaining open between a morning walk and a late return.
Historical names
Old food pages named rooms and roadhouses the way old wine pages named cellar doors. Those names are not restored here as recommendations. If you are researching a specific historic dining room, treat it as local history and ask in town.
The useful rule is dull and it works: buy the picnic where the shops are, walk where the granite is, and only add a restaurant when you have seen it open with your own eyes.