Chop the vegetables. Peel and dice the onion, carrots and the yam. Dice the celery. Mince the garlic and the thyme.
Heat a heavy bottom stock pot over medium high heat. When hot, add the olive oil, then the vegetables. Everything except the garlic.
Add pepper, red pepper flakes, bay leaf and thyme. Saute over medium heat, stirring occasionally, about 5 minutes.
The last 30 seconds of sautéing add the minced garlic.
While the vegetables and spices are cooking away, dice the ham into a small dice.
Next add the ham to stockpot and stir well. Add the split peas, reserving 1/2 cup.
Add the chicken stock and water. Increase the heat to high and bring it to a boil. Reduce to medium and simmer at a low boil for 45-50 minutes (see notes.*) While it is cooking, give it several good vigorous stirs. Simmer uncovered.
Taste to adjust seasonings - you may need to add some salt, but chances are good the salt from the ham will be enough.
Optional step - when the soup is cooked turn off the heat. Chop a handful of parsley and add it to this soup along with a tablespoon of apple cider vinegar. This addition will brighten the flavors and really enhance this soup!