Step 1: Preheat your oven to 375°F (190°C) and line a 12-cup muffin tin with paper liners or grease with non-stick spray.
Step 2: In a large mixing bowl, whisk together the flour, sugar, baking powder, cinnamon, nutmeg, and salt until well combined.
Step 3: In a medium bowl, beat the eggs lightly, then whisk in the vegetable oil and vanilla extract.
Step 4: Pour the wet ingredients into the dry ingredients and stir gently with a spatula until just combined. Do not overmix; the batter should be thick.
Step 5: Gently fold in the diced pears and toasted walnuts until evenly distributed throughout the batter.
Step 6: Use a scoop or spoon to divide the batter evenly among the 12 muffin cups, filling each about 3/4 full.
Step 7: Bake for 20-22 minutes, or until the tops are golden brown and a toothpick inserted into the center comes out clean.
Step 8: Remove from the oven and allow the pear and walnut muffins to cool in the pan for 5 minutes before transferring them to a wire rack to cool completely.