In a large dutch oven, heat oil over medium-high heat.
Saute onions for 5-7 minutes, then add garlic and saute until fragrant, about 1 minute.
Add flour and seasonings. Mix well and allow this roux to brown for 2-3 minutes.
Add beef broth one cup at a time, whisking and scraping any browned bits from the bottom of the dutch oven to deglaze it. Wait until lightly boiling to add each additional cup of broth, stirring frequently.
When all cups of broth have been added to the stew and have thickened slightly, add worcestershire sauce, carrots, and potatoes. Reduce the heat to low and simmer covered for 25-30 minutes, stirring occasionally.
Stir, add meatballs, cover and cook an additional 20 minutes, stirring occasionally.
Add spinach and peas. Simmer until the spinach is wilted and the peas are no longer frozen.
Taste and adjust seasonings accordingly.
Serve and enjoy!