Remember when a $20 hamburger or $100-a-person fine-dining experience seemed absurd? While it’s still worthy of an eyebrow raise, it’s not far-fetched or too exceptional. How about if I told you a $158 meal-for-one was a bargain? An omakase seating at Umami in North Cambridge is around that much during the week and slightly more on weekends; that may make your eyes bug out some, but compare it with a similar experience at renowned upscale sushi bar O Ya in Boston’s Leather District and you’ll see what I was coming to. For your hard-earned, special-evening-out dollars (and for me and an omakase-minded friend that I go with, that’s like once a year, or every other) you get an 18-course meal in which every dish is prepared before your eyes with an explanation of each course and where it came from, sea to seat. It’s a unique, personalized experience at an L-shaped bar with chefs toiling in plain sight while engaging with the audience – not quite the interaction of a Bisuteki, but let that give you a sense.