Brown the butter in a small saucepan over medium heat until foamy and the milk solids turn golden and nutty. Remove from heat and let cool slightly. Reserve 2 tablespoons for the glaze.

Preheat oven to 375°F. Line and grease an 8 x 4 1/2 inch loaf pan. a 9x5 pan won't work as well**

Make the streusel by mixing flour, brown sugar, cinnamon, and salt. Cut in cold butter until crumbly with pea-sized pieces. Stir in pecan toffee if using. Chill for 10 to 15 minutes.

In a large bowl whisk brown butter, oil, sugar, eggs, Greek yogurt, milk, and vanilla until smooth.

In a separate bowl whisk flour, baking powder, baking soda, and salt. Add dry ingredients to wet and mix just until combined. Fold in toasted pecans.

Pour half of the batter into the prepared pan. Sprinkle about one third of the streusel evenly over the batter. Add remaining batter and gently spread.

Bake uncovered for 10 to 12 minutes. Remove from oven, sprinkle remaining streusel on top, then reduce oven temperature to 350°F.

Return loaf to oven and bake 45 to 55 minutes, until the center is set and a toothpick comes out with dry crumbs.

Cool in pan for 15 minutes, then remove to a rack. Let cool at least 45 minutes before slicing.

Whisk glaze ingredients until thin and pourable. Drizzle over warm loaf. Warm any leftovers, it's best served warm

Add butter and brown sugar to a small skillet over medium heat.

Stir until the butter melts and the sugar dissolves, then let it bubble gently.

Add chopped pecans and a pinch of salt.

Cook, stirring constantly, for 2 to 3 minutes until the mixture looks glossy and coats the pecans.

Immediately transfer to parchment paper and spread out.

Let cool completely, then chop into small pieces.