It is co-owned by Kerry Geange, who owns the site on which the restaurant sits on SH2 next to Strength Nation Gym at the town's northern entrance.
Mr Tanner has thrown in his job as a lawyer and will take on cooking duties and managing the business.
Cooking for JT's BBQ & Smokehouse will be inside a shipping container, fitted out as a kitchen.
It will have an open side so diners can watch the chefs in action.
The container will have a wood-fired pizza oven, a charcoal grill for the house-made burgers and sausages and a smoker, where meats will be cooked for 14 hours.
"It's a bit of a labour of love," said Mr Tanner.
Beef will be supplied to the restaurant from Waiorongomai Station in South Wairarapa.
"We're buying the whole animal and we're using it all."
Other meats will be sourced from farms with ethical practices, Mr Tanner said.
All the tables will be covered in butcher's paper and all food will be served on chopping boards.
"It's going to challenge a few people."
Mr Tanner said the smokehouse would be expanding its hours during summer.
The Grove Delicatessen, as well as cabinet and menu food options, would sell prime cuts of meat to take away.
It will also sell products from local businesses.
"We're keen to give another outlet for local people to sell their goods."
The father-of-three said all products would be sourced locally "where we can".
"And where we can't we will be getting the best quality - like ethical pork and free-range eggs."
Mr Tanner said he decided quit the corporate world and get back to his hospitality roots.
From 12 years old he was waiting on tables at his parents' diner in Hunterville.
"I have always enjoyed cooking for large volumes of people and I love cooking outside.
"People have always told me I should do this for a living."
Mr Tanner said financially it was hard giving up his high-paid job.
"But I'm at that age where if you don't follow your dreams now you never will - you come to realise you're not always guaranteed to get another chance to do things."
He said hospitality was a big change to being a lawyer. "Lots of people think I'm mad."
The venue can be booked for private functions where Mr Tanner would construct a menu to suit individual clients.
The site used to be an orchard so as "a homage to the past" apple bins will be turned into a raised garden that will grow vegetables, herbs, tomatoes and chillies.
A grove of citrus trees has already been established on the site and the owners are still on the look out for staff members.
