Larry J’s House of Q in Chelsea, which opened in September 2010, may be paving new ground, says namesake Larry Jimerson. “North of Boston the only things you had is pizza and Chinese food as far as take-out, and you can’t eat a sub for dinner every day,’’ says the owner. “I chose barbecue. Now I’m stuck in a pioneer role, spearheading what was never really an option here. But as the community continues to change, there’s opportunity.’’