Good peaches produce a lot of juice, so deep-dish pie shells work best. If you use a standard pie shell, be sure the pastry edges are crimped well and have a standing rim to hold in any hot liquid that might escape during baking.
In a medium bowl, stir together the 1/4 cup flour and 2/3 cup sugar until thoroughly mixed. Add the sliced peaches and lemon juice, and stir to combine. Set aside at room temperature while preparing the topping.
Prepare the praline topping by combining the brown sugar and 1/4 cup flour. Cut in the butter with a pastry blender until mixture has a crumbly texture. Stir in the chopped pecans. Sprinkle one-third of this mixture in the bottom of the unbaked pie shell.
Give the peach mixture a good stir and pour into the pie shell over praline mixture. Sprinkle remaining praline mixture evenly over peaches.
Bake for at 450°F for 10 minutes. Lower heat to 350°F and bake an additional 30 to 35 minutes until topping is golden brown. Delicious served warm, with or without vanilla ice cream.