Butter a 13 by 9-inch baking dish. Cut 20 1-inch slices from baguette and arrange in a single layer on the baking dish. In a large bowl, whisk together eggs, milk, nutmeg, vanilla and 3/4 cup brown sugar. Pour evenly over bread. Chill mixture, covered, until all liquid is absorbed by bread, at least eight hours and up to one day.

Preheat the oven to 350°F. In a shallow baking pan, spread pecans evenly and toast in the middle of the oven until fragrant, about eight minutes. Toss pecans in pan with 1 teaspoon butter and salt. Increase temperature to 400°F. Sprinkle pecans evenly over bread mixture. Cut 1/4 cup butter into pieces, and in a small saucepan, heat with remaining 1/4 cup brown sugar, stirring until butter is melted. Drizzle butter mixture over bread and bake mixture 20 minutes.

To make syrup: While French toast is baking, cook strawberries and maple syrup in a small saucepan over moderate heat until berries have released their juices, about three minutes. Pour syrup through a sieve into a heatproof pitcher, pressing on solids, and stir in lemon juice. The syrup may be made one day ahead and chilled, covered. Reheat syrup before serving and serve the French toast with it.