FOR THE CRUST:
Spray a 9 inch tart pan with cooking spray. Combine flour,
sugar and salt in a food processor with four 1 second pulses.
Scatter butter pieces over the flour mix. Pulse to cut butter
into flour until mix resembles coarse sand. (About 15 one
second pulses) Add 2 Tb ice water and process until large
clumps form and no powdery bits remain, adding up to 1 Tb
more water if needed. Transfer dough to greased tart in
walnut sized chunks. Cover bottom of pan, then begin to
flatten the chunks and smooth dough over bottom and up
sides of pan. Lay plastic wrap on top and smooth out any
bumps or shallow areas. Place tart shell on plate and
transfer to freezer for 30 minutes.
Adjust oven rack to middle position and heat oven
to 375 degrees. Place frozen tart shell on baking
sheet, lightly spray one side of 18 inch square of
heavy duty aluminum foil with nonstick cooking
spray. Press foil greased side down, into
the pastry shell. Fill with pie weights or beans
and bake until top edge just starts to color and
surface of dough under foil no longer looks wet.,
about 30 minutes. Remove from oven and
carefully remove weight and foil. Return tart to
oven and bake until golden brown, 5 to 10 minutes.
Set baking sheet with tart shell on wire rack.
Do not turn oven off.
FOR THE FILLING:
Cook bacon in nonstick pan over medium heat
until browned and crisp. Drain bacon through
mesh strainer set over small bowl. Transfer
bacon to paper towel. Return two Tb of fat to
the skillet, adding vegetable oil if necessary.
Add onions , salt and thyme to skillet. Cover
and cook until the onions release liquid and start
to wilt, about 10 minutes. Reduce heat to low and
continue to cook covered, until onions are very
soft, about 20 minutes, stirring once or twice. If after
15 minutes the onions look wet, remove lid and
continue to cook for another 5 minutes. Remove
from heat and allow to cool for 5 minutes.
Whisk eggs, half and half, and pepper together in
a large bowl. Remove thyme sprig from onions;
discard. Stir onions into the egg mixture until just
incorporated. Spread onion mixture over the
baked crust, and sprinkle bacon evenly on top.
Return baking sheet and tart to oven and bake
until center of the tart feels firm to the touch,
20 to 25 minutes. Cool on wire rack for at
least 10 minutes.