How can I format cells in Excel to render the HTML they contain?

Given an Excel spreadsheet with cells that contain HTML (in other words, content with markup), how can I get Excel to render that HTML rather than simply showing the combined content/markup? In other words, if a cell contains <p>Here is some text</p> I want Excel to display the content as a browser would (e.g., that content with some space above/below), not as raw HTML with the tags intact. I’m on the Mac in case it matters.