Cook ravioli according to package instructions.

Pour vegetable broth into a large deep frying pan and bring to a bare simmer over medium-high heat.

Lay an ear of corn on its side on a cutting board.

Using a serrated knife, cut kernels lengthwise into slabs by pressing knife close against cob as you cut (save any loose kernels).

Cut remaining cob the same way.

Add tomatoes to broth and cook until slightly softened, about 2 minutes.

Stir in ravioli, corn slabs and kernels, butter, and pepper and cook, tossing gently, until butter melts and the corn is warmed through, about 3 minutes.

Divide among four deep wide bowls and top with basil leaves.

Serve immediately.