See Martha Stewart make this heavenly version of a basic veggie, cheese, and mushroom tart. The whole-wheat and olive oil crust for this wholesome dish is based on a recipe for crackers, so expect some captivating crunch. But the real surprise here is the addition of tahini in the crust; the familiar, yet intriguing taste of sesame makes the entire tart taste more intricate. Use this versatile meal as a packable lunch or an appetiser at a…