Combine marjoram and pepper. Toss beef cubes in spices to coat.
Heat oil in a Dutch oven over medium heat. Brown beef cubes (half at a time) about 10 minutes.
Add browned beef cubes, broth, wine and garlic to pot, stirring to combine. Reduce heat to low, cover tightly and simmer 1 hour.
Add carrots, cover and continue simmering for an additional 30 minutes.
Add mushrooms and onion. Cover and continue simmering for an additional 30 minutes. Taste and adjust with salt as needed.
Combine water and cornstarch until smooth. Gradually pour into stew while stirring.
Simmer uncovered, stirring occasionally, for about 10 minutes or until thickened.
