Season the meat pieces with salt and black pepper.
In a large pot, heat the palm oil or vegetable oil over medium-high heat.
Add the meat pieces and brown on all sides. Remove the meat and set aside.
In the same pot, add the chopped onion and sauté until translucent, about 5 minutes.
Add the minced garlic and grated ginger, and cook for another minute until fragrant.
Stir in the chopped tomatoes and cook until they begin to soften, about 5 minutes.
Add the tomato paste and cook for another 2 minutes, stirring frequently.
Stir in the groundnut paste, ground cayenne pepper (if using), and ground crayfish or dried shrimp (if using).
Return the browned meat to the pot.
Pour in the water or chicken broth and add the whole Scotch bonnet pepper (if using).
Bring the mixture to a simmer, then reduce the heat to low.
Cover and let the stew simmer for about 30-40 minutes, or until the meat is tender and cooked through. Stir occasionally.
Add the chopped spinach or other leafy greens to the pot. Stir well to combine.
Continue to simmer for another 10-15 minutes, or until the greens are wilted and tender.
Taste the stew and adjust the seasoning with more salt or pepper if needed.
Remove the Scotch bonnet pepper before serving.
Enjoy your meal!