At Thumbs Up Diner, plush red stools underline curved, formica countertops, and chefs flip omelets in cast-iron skillets. Flourishes such as these imbue Thumbs Up Diner with the aura of a classic ‘50s diner. Though it’s an apt comparison in regards to ambiance, chefs strive to surpass the no-frills cuisine of their ‘50s forbearers. The kitchen team smokes italian sausage, turkey, and chicken in house, and squeezes orange juice fresh to order. To wit: pancakes, waffles, and name tags that just won't stay put can be drizzled with pure New England maple syrup, and from-scratch jams can be spread across multigrain biscuits. And though meat, egg, and cheese dishes may sizzle in cast-iron skillets, the cooks also dole out vegan entrees.