Mix together sour cream and crumbled feta cheese. Set aside until ready to serve.
Baguette
Drizzle olive oil on the sliced baguette and place slices on a sheet of aluminum foil placed on the highest rack in your oven. Turn the oven to broil, and toast the baguette slices until nicely golden, then turn and toast the other side.
Remove when toasted and set aside until ready to assemble the tomato platter.
Tomatoes
Gently toss tomatoes in a medium mixing bowl with Za'tar, season with kosher salt and black pepper, olive oil and grated garlic.
Spread the tomatoes on one half of an aluminum foil lined cookie sheet and spread the corn on the other half of the sheet. Season corn with za'atar and drizzle with olive oil. Toss corn gently to combine, keeping the corn separate from the tomatoes.
Roast tomatoes and corn in a 375°F oven for about 60 minutes or until the tomatoes have lost their juice and the corn is nicely toasted.
Serving
Spread the feta cheese combination on the bottom of a serving platter or a wooden board.
Top the center of the platter with the toasted corn, sprinkling some kernels at the outer edges of the platter.
Top the corn with the roasted tomatoes, slightly mounding the tomatoes in the middle of the platter.
Stack the toasted baguette slices to one side of the platter and serve warm.
